Image generating device

ABSTRACT

An optical device may include an optical fiber having a fixed end and a free end; a first actuator positioned at a actuator position between the fixed end and the free end and configured to apply a first force on the actuator position of the optical fiber such that a movement of the free end of the optical fiber in a first direction is caused, wherein the first direction is orthogonal to a longitudinal axis of the optical fiber; and a deformable rod disposed adjacent to the optical fiber, and having a first end and a second end, wherein the first end is connected to a first rod position of the optical fiber and the second end is connected to a second rod position of the optical fiber.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of U.S. ProvisionalApplication No. 62/842,365, filed on May 2, 2019, Korean PatentApplication No. 10-2019-0112711, filed on Sep. 11, 2019, the disclosureof which is incorporated herein by reference in its entirety.

BACKGROUND 1. Field

Embodiments relate to an image generating device for observing theinside of an object in real-time and an image generation method usingthe same.

2. Discussion of Related Art

Optical devices are for emitting light to an object to observe theinside and outside of the object and are widely used in various medicalfields, biological research, and industrial fields.

In particular, endoscopes, which are being widely used in the medicalfield, have the advantage of observing and diagnosing pathologicalconditions in real-time by being inserted into human bodies in anon-invasive manner. However, typical endoscopes can observe onlysurfaces of living bodies and thus have a disadvantage in that it isnecessary to detach and check a part of biological tissue using aseparate optical device, a chemical biopsy, and the like in order toobserve the inside and characteristics of cells.

The disclosure of this section is to provide background informationrelating to the invention. Applicant does not admit that any informationcontained in this section constitutes prior art.

SUMMARY

One aspect of the invention provides endomicroscopes developed forobserving the characteristics of living bodies in real-time, and alsominiaturized while providing high-resolution images in order to observepathological conditions through a minimal incision in real-time.

The following embodiments are directed to providing a high-resolutionimage by emitting a preset scanning pattern to an object.

Also, the following embodiments are directed to providing ahigh-resolution image by changing the phase of the scanning pattern inreal-time.

Also, the following embodiments are directed to making an input signalfor driving an optical fiber in the scanning pattern correspond to anoutput signal by which the optical fiber is actually driven by attachinga structure.

Also, the following embodiments are directed to preventing breakage ofthe structure by separating the structure from an end of the opticalfiber when the optical fiber is driven.

Also, the following embodiments are directed to adjusting an aspectratio of an output image by adjusting the voltage level of an opticalfiber input signal.

Also, the following embodiments are directed to calibrating the phase ofan image for the first time when a probe is mounted on a mounting stand.

Also, the following embodiments are directed to calibrating the phase ofan output image by using the difference between light intensity valuesobtained at one pixel position.

Also, the following embodiments are directed to providing a method ofdiscovering a phase for calibrating an output image by using apredetermined phase change period.

According to an embodiment, an optical device, comprising: an opticalfiber having a fixed end and a free end; a first actuator positioned ata actuator position between the fixed end and the free end andconfigured to apply a first force on the actuator position of theoptical fiber such that a movement of the free end of the optical fiberin a first direction is caused, wherein the first direction isorthogonal to a longitudinal axis of the optical fiber; and a deformablerod disposed adjacent to the optical fiber, and having a first end and asecond end, wherein the first end is connected to a first rod positionof the optical fiber and the second end is connected to a second rodposition of the optical fiber, wherein the first rod position and thesecond rod position of the optical fiber are positioned between theactuator position and the free end, wherein the deformable rod issubstantially parallel to the optical fiber from the first rod positionof the optical fiber to the second rod position of the optical fiber,and wherein, in the cross section perpendicular to the longitudinal axisof the optical fiber, the deformable rod is arranged such that an anglebetween a virtual line connected from the first end of the deformablerod to the first rod position of the optical fiber and the firstdirection is within a predetermined angle, whereby the movement of theoptical fiber in a second direction perpendicular to the first directionis limited when the free end of the optical fiber moves in the firstdirection as the first actuator applies the first force on the actuatorposition of the optical fiber, can be provided.

According to another embodiment, an optical device comprising: anoptical fiber having a fixed end and a free end, and configured toirradiate a predetermined scanning pattern; a first actuator positionedat a actuator position between the fixed end and the free end andconfigured to apply a first force on the actuator position of theoptical fiber such that a movement of the free end of the optical fiberin a first direction is caused; a second actuator configured to apply asecond force on the actuator position of the optical fiber such that amovement of the free end of the optical fiber in a second direction iscaused, wherein the first direction is orthogonal to a longitudinal axisof the optical fiber, and the second direction is perpendicular to thefirst direction; a deformable rod having a first end and a second end,and disposed in the first direction or the second direction adjacent tothe optical fiber, wherein the first end is fixed to a first rodposition of the optical fiber and the second end is fixed to a secondrod position of the optical fiber, wherein the first rod position andthe second rod position of the optical fiber are positioned between theactuator position and the free end; and a controller configured to applya first driving frequency to the first actuator and a second drivingfrequency to the second actuator; wherein an aspect ratio of thescanning pattern irradiated by the optical fiber is associated with theattachment direction of the deformable rod, and wherein the controlleradjusts the aspect ratio of the scanning pattern by applying a firstvoltage to the first actuator and a second voltage to the secondactuator, can be provided.

According to another embodiment, an image generating device comprisingan irradiation unit configured to irradiate light to an object, a lightreceiving unit configured to receive the returned light from the objectand obtain a signal based on the returned light, and a controllerconfigured to generate an image based on the signal obtained from thelight receiving unit, the device comprising: an optical fiber having afixed end and a free end; a first actuator positioned at a actuatorposition between the fixed end and the free end and configured to applya first force on the actuator position of the optical fiber such that amovement of the free end of the optical fiber in a first direction iscaused; a second actuator configured to apply a second force on theactuator position of the optical fiber such that a movement of the freeend of the optical fiber in a second direction is caused, wherein thefirst direction is orthogonal to a longitudinal axis of the opticalfiber, and the second direction is perpendicular to the first direction;a deformable rod having a first end and a second end, and disposed inthe first direction or the second direction adjacent to the opticalfiber, wherein the first end is fixed to a first rod position of theoptical fiber and the second end is fixed to a second rod position ofthe optical fiber, wherein the first rod position and the second rodposition of the optical fiber are positioned between the actuatorposition and the free end, wherein an aspect ratio of the generatedimage is associated with the attachment direction of the deformable rod,and wherein the controller adjusts the aspect ratio of the generatedimage by applying a first voltage to the first actuator and a secondvoltage to the second actuator, may be provided.

According to another embodiment, an optical device, comprising: anoptical fiber having a fixed end and a free end; a first actuatorpositioned at a actuator position between the fixed end and the free endand configured to apply a first force on the actuator position of theoptical fiber such that a movement of the free end of the optical fiberin a first direction is caused; a second actuator configured to apply asecond force on the actuator position of the optical fiber such that amovement of the free end of the optical fiber in a second direction,wherein the first direction is orthogonal to a longitudinal axis of theoptical fiber, and the second direction is perpendicular to the firstdirection; a mass having a preselected size, and disposed between thefixed end and the free end of the optical fiber; and a housing receivingthe optical fiber, the first actuator and the second actuator, whereinthe optical fiber vibrates inside the housing by the first force and thesecond force, and a maximum movement range of the optical fiber dependson the location of the mass, wherein the mass is located away from thefree end of the optical fiber by a buffer distance to prevent the massfrom colliding with an inner wall of the housing and being damaged whenthe optical fiber vibrates, and wherein the buffer distance is set basedon at least one of the size of the mass, an inner diameter of thehousing, and the maximum movement range of the optical fiber, andwherein the buffer distance is determined at least one of the followingis less than ½ of an inner diameter of the housing: the maximum movementrange of the optical fiber from the center of the inner diameter and amaximum movement range of the mass from the center of the innerdiameter, may be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set based on the first signal, the second signal andthe light receiving signal, wherein the control module configured toobtain a second data set based on the first data set by adjusting atleast one of the first phase component of the first signal and thesecond phase component of the second signal, wherein the control moduleconfigured to select from the first data set and the second data setbased on predetermined criteria, and wherein the image of the object isgenerated based on the selected data set, can be provided.

According to another embodiment, an image generating method forobtaining an image of an object, comprising: generating a first signalhaving a first frequency component and a first phase component for afirst axis direction, and a second signal having a second frequencycomponent and a second phase component in a second axis directionthrough a control module; obtaining light receiving signal based onreturned light from the object, through a light receiving unit;obtaining a first data set based on the first signal, the second signaland the light receiving signal, obtaining a second data set based on thefirst data set by adjusting at least one of the first phase component ofthe first signal and the second phase component of the second signal,selecting from the first data set and the second data set based onpredetermined criteria, and generating the image of the object based onthe selected data set, can be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set based on the first signal, the second signal andthe light receiving signal, wherein the control module configured toobtain a second data set based on the first data set by adjusting atleast one of the first phase component of the first signal and thesecond phase component of the second signal using a first amount ofphase adjustment, wherein the control module configured to select fromthe first data set and the second data set based on predeterminedcriterion, wherein the control module configured to obtain a third dataset based on the second data set by adjusting phase component of atleast one of signals used for obtaining the second data set using thefirst amount of phase adjustment, when the second data set is selectedamong the first data set and the second data set, wherein the controlmodule configured to select from the second data set and the third dataset based on the predetermined criterion, and wherein the control moduleconfigured to generate the image of the object based on the second dataset, when the second data set is selected among the second data set andthe third data set, can be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set using the first signal, the second signal andthe light receiving signal, wherein the control module adjusts a phasecomponent of at least one of the first signal or the second signal by afirst amount of phase adjustment by plurality of times, wherein thecontrol module configured to obtain a plurality of data sets using eachof the signal adjusted by the plurality of times and a light receivingsignal adjusted by the plurality of times, wherein the control moduleconfigured to obtain a data set using at least one of the signal and thelight receiving signal, when each time at least one of the signal isadjusted by the first amount of phase adjustment, wherein the controlmodule configured to obtain a nth data set using at least one of thesignal which the phase component is adjusted by the first amount ofphase adjustment n times and the light receiving signal, when at leastone of the signal is adjusted by the first amount of phase adjustment ntimes, wherein the control module adjusts a phase component of at leastone of the first signal or the second signal by the first amount ofphase adjustment by (n+1) times, when the nth data set is morecorresponding to the predetermined criterion than a (n−1)th data setobtained previously than the nth data set, wherein the (n−1)th data setis obtained when the phase component of at least one of the first signaland the second signal is adjusted by the first amount of phaseadjustment (n−1) times, wherein the control module configured to obtaina (n+1)th data set using at least one of the signal which the phasecomponent is adjusted by the first amount of phase adjustment by (n+1)times and the light receiving signal, and wherein the control moduleproducing the image based on at least one of the signal which the phasecomponent is adjusted by the first amount of phase adjustment (n−1)times, when the (n−1)th data set is more corresponding to thepredetermined criterion than the nth data set, can be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first phase adjusted signal which is a sum of a n times of afirst amount of phase adjustment and the first phase component of thefirst signal, wherein the control module configured to obtain a secondphase adjusted signal which is a sum of a m times of a first amount ofphase adjustment and the second phase component of the second signal,wherein the n and m are different integer and larger than 1, and whereinthe control module configured to generate the image using a first dataset obtained based on the first phase adjusted signal, when the firstdata set obtained based on the first phase adjusted signal and thesecond signal is more corresponding to a predetermined criterion than asecond data set obtained based on the second phase adjusted signal andthe second signal, can be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured togenerate and output a first image using the first signal and the secondsignal at a first point of time, wherein at least one of the firstsignal and the second signal is adjusted during a predetermined timeperiod after the first point of time, wherein the control modulegenerates and outputs a second image using at least one of the phaseadjusted signal at a second point of time after the predetermined timeperiod, wherein a difference between the phase of the first signal atthe first point of time and the phase of the first signal at the secondpoint of time and a difference between the phase of the second signal atthe first point of time and the phase of the second signal at the secondpoint of time are different by substantially an integer multiple of afirst amount of phase adjustment, and wherein the first amount of phaseadjustment is determined based on the first frequency component and thesecond frequency component, can be provided. According to anotherembodiment, an image generating method for obtaining an image of anobject, comprising: generating a first signal having a first frequencycomponent and a first phase component for a first axis direction, and asecond signal having a second frequency component and a second phasecomponent in a second axis direction through a control module; obtaininglight receiving signal based on returned light from the object, througha light receiving unit; obtaining a first data set based on the firstsignal, the second signal and the light receiving signal; obtaining asecond data set based on the first data set by adjusting at least one ofthe first phase component of the first signal and the second phasecomponent of the second signal using a first amount of phase adjustment;selecting from the first data set and the second data set based onpredetermined criterion; obtaining a third data set based on the seconddata set by adjusting phase component of at least one of signals usedfor obtaining the second data set using the first amount of phaseadjustment, when the second data set is selected among the first dataset and the second data set; selecting from the second data set and thethird data set based on the predetermined criterion; generating theimage of the object based on the second data set, when the second dataset is selected among the second data set and the third data set, can beprovided.

According to another embodiment, a light irradiating unit, comprising: acontrol module configured to generate a first signal having a firstfrequency component and a first phase component for a first axisdirection, and a second signal having a second frequency component and asecond phase component for a second axis direction; an emitting unitconfigured to emit light to the object using the first signal and thesecond signal; and a light receiving unit configured to obtain lightreceiving signal based on returned light from the object; wherein thecontrol module configured to obtain a first data set based on the firstsignal, the second signal and the light receiving signal, wherein thecontrol module configured to obtain a second data set based on the firstdata set by adjusting at least one of the first phase component of thefirst signal and the second phase component of the second signal using afirst amount of phase adjustment, wherein the control module configuredto select from the first data set and the second data set based onpredetermined criterion, wherein the control module configured to obtaina third data set based on the second data set by adjusting phasecomponent of at least one of signals used for obtaining the second dataset using the first amount of phase adjustment, when the second data setis selected among the first data set and the second data set, whereinthe control module configured to select from the second data set and thethird data set based on the predetermined criterion, and wherein thecontrol module configured to generate the image of the object based onthe second data set, when the second data set is selected among thesecond data set and the third data set, can be provided.

According to another embodiment, an optical device for emitting light toan object, comprising: a control module configured to generate actuatingsignals; and an emission unit configured to receive the actuatingsignals and emit light to the object based on the actuating signals;wherein when the emission unit receives a first actuating signal havinga first actuating frequency and a first phase and a second actuatingsignal having a second actuating frequency and a second phase among theactuating signals, the emission unit emits the light with a firstscanning pattern based on the first actuating signal and the secondactuating signal, wherein when the emission unit receives a thirdactuating signal having the third actuating frequency and a third phaseand a fourth actuating signal having a fourth actuating frequency and afourth phase among the actuating signals, the emission unit emits thelight with a second scanning pattern based on the third actuating signaland the fourth actuating signal, wherein the first phase and the secondphase have different by a first phase difference, wherein the thirdphase and the fourth phase have different by a second phase difference,and wherein the control module configured to generate the actuatingsignals by setting difference between the first phase difference and thesecond phase difference being n times of a predetermined phase, can beprovided.

According to another embodiment, an light emitting method by an opticaldevice for emitting light to an object, wherein the optical devicecomprising a control module configured to generate actuating signals andan emission unit configured to receive the actuating signals and emitlight to the object based on the actuating signals, the light emittingmethod comprising: receiving a first actuating signal having a firstactuating frequency and a first phase and a second actuating signalhaving a second actuating frequency and a second phase among theactuating signals, the emission unit emits the light with a firstscanning pattern based on the first actuating signal and the secondactuating signal, through the emission unit; and receiving a thirdactuating signal having the third actuating frequency and a third phaseand a fourth actuating signal having a fourth actuating frequency and afourth phase among the actuating signals, the emission unit emits thelight with a second scanning pattern based on the third actuating signaland the fourth actuating signal, through the emission unit; wherein thefirst phase and the second phase have different by a first phasedifference, wherein the third phase and the fourth phase have differentby a second phase difference, wherein the control module configured togenerate the actuating signals by setting difference between the firstphase difference and the second phase difference being n times of apredetermined phase, can be provided.

According to another embodiment, a mounting device for mounting an imagegenerating device comprising a probe, emitting light to an object froman one end of the probe and receiving light returning from the object atthe one end of the probe, the mounting device comprising: a housingconfigured to hold at least part of the image generating device, whereinthe at least part of the image generating device includes the one end ofthe probe; and a reference image providing unit configured to provide atleast one of a reference image such that the image generating deviceperforms a phase adjustment of an actuating signal related to positionsof the emitted light on the object from the one end of the probe whenthe housing holds the at least part of the image generating device;wherein the reference image providing unit adjusts a position of thereference image for corresponding a distance between the one end of theprobe and the reference image to a focal length of the probe, can beprovided.

According to another embodiment, a mounting device for mounting an imagegenerating device comprising a probe, emitting light to an object froman one end of the probe and receiving light returning from the object atthe one end of the probe, comprising: a housing configured to hold atleast a part of the image generating device, wherein at least the partof the image generating device includes the one end of the probe; and areference image providing unit configured to provide a plurality of areference image for performing a phase adjustment of an actuating signalwhich determines a position of light emission on the object from the oneend, when the housing holds at least of the part of the image generatingdevice; wherein the reference image providing unit comprises a pluralityof layers including each of the plurality of reference image forcorresponding a distance between the one end of the probe and thereference image to a focal length of the probe, can be provided.

According to another embodiment, an image generating device forobtaining an image of an object, comprising: a control module configuredto generate a first signal having a first frequency component and afirst phase component for a first axis direction, and a second signalhaving a second frequency component and a second phase component for asecond axis direction; an emitting unit configured to emit light to theobject using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module performs afirst phase adjustment at least one of the first signal and the secondsignal using a light receiving signal based on light returning from areference image, when light is emitted from the emitting unit to thereference image arranged in a mounting device, at a state of theemitting unit mounted in the mounting device, wherein the mountingdevice has the reference image inside, wherein the control modulerepeatedly performs a second phase adjustment periodically using thelight receiving signal based on light returning from the referenceimage, when light is emitted from the emitting unit to the referenceimage arranged in a mounting device, at a state of the emitting unit notmounted in the mounting device, wherein the second phase adjustment isperformed based on a phase at least one of the first signal and thesecond signal adjusted by the first phase adjustment, can be provided.

According to another embodiment, a phase adjusting method by an imagegenerating device for obtaining an image of an object, wherein the imagegenerating device comprising a control module configured to generate afirst signal having a first frequency component and a first phasecomponent for a first axis direction, and a second signal having asecond frequency component and a second phase component in a second axisdirection; an emitting unit configured to emit light to the object usingthe first signal and the second signal and a light receiving unitconfigured to obtain light receiving signal by returning light from theobject, based on the light emitted by the emitting unit, the phaseadjusting method comprising: performing a first phase adjustment atleast one of the first signal and the second signal using a lightreceiving signal based on light returning from a reference image, whenlight is emitted from the emitting unit to the reference image arrangedin a mounting device, at a state of the emitting unit mounted in themounting device, wherein the mounting device has the reference imageinside, through the control module; and repeatedly performing a secondphase adjustment periodically using the light receiving signal based onlight returning from the reference image, when light is emitted from theemitting unit to the reference image arranged in a mounting device, at astate of the emitting unit not mounted in the mounting device, throughthe control module; wherein the second phase adjustment is performedbased on a phase at least one of the first signal and the second signaladjusted by the first phase adjustment, can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the presentinvention will become more apparent to those of ordinary skill in theart by describing exemplary embodiments thereof in detail with referenceto the accompanying drawings, in which:

FIG. 1 is a diagram for exemplarily describing an environment in whichan image generating device is used according to an embodiment of thepresent invention;

FIG. 2 is a block diagram for exemplarily describing a configuration ofan image generating device according to an embodiment of the presentinvention;

FIG. 3 is a diagram illustratively showing the form of a scanning moduleaccording to an embodiment of the present invention;

FIG. 4 is a diagram schematically showing various scanning patternsaccording to an embodiment of the present invention;

FIG. 5 is a block diagram for exemplarily describing a configuration ofan image processing module 200 according to an embodiment of the presentinvention;

FIG. 6 is a block diagram for exemplarily describing an internalconfiguration of a scanning module 110 according to an embodiment of thepresent invention;

FIG. 7 is a sectional view for exemplarily describing an internalconfiguration of the scanning module 110 according to an embodiment ofthe present invention;

FIG. 8 is a diagram illustratively showing a beam that is output when anoptical fiber is processed into a conical or hemispherical shapeaccording to another embodiment of the present invention;

FIGS. 9 and 10 are diagrams for exemplarily describing a configurationof a lens module according to an embodiment of the present invention;

FIG. 11 is a diagram for exemplarily describing a structure of ascanning unit according to an embodiment of the present invention;

FIG. 12 is a graph for exemplarily describing design conditions of thescanning unit according to an embodiment of the present invention;

FIGS. 13 and 14 are diagrams for exemplarily describing an attachmentposition of a mass M according to an embodiment of the presentinvention;

FIG. 15 is a graph for describing frequency separation according to anembodiment of the present invention;

FIGS. 16 to 18 are diagrams for exemplarily describing a structure of adriving range adjustment means according to an embodiment of the presentinvention;

FIG. 19 is a diagram for exemplarily describing cross-coupling accordingto an embodiment of the present invention;

FIG. 20 is a diagram for exemplarily describing a vibration principle ofan optical fiber according to another embodiment of the presentinvention;

FIGS. 21 and 22 are diagrams for describing an attachment position of adeformable rod according to embodiments of the present invention;

FIG. 23 is a graph for describing frequency separation according to anembodiment of the present invention;

FIG. 24 is a diagram for exemplarily describing Lissajous scanningaccording to an embodiment of the present invention;

FIG. 25 is a diagram for exemplarily describing an attachment anglerange of a deformable rod according to an embodiment of the presentinvention;

FIG. 26 is a diagram for exemplarily describing a coupling erroraccording to an embodiment of the present invention;

FIG. 27 is a graph for exemplarily describing an attachment angle rangeof a deformable rod according to an embodiment of the present invention;

FIGS. 28 to 30 are diagrams showing frequency characteristics accordingto an attachment direction of the above-described deformable rod;

FIG. 31 is a flowchart for exemplarily describing an aspect ratiocorrection method according to an embodiment of the present invention;

FIGS. 32 to 34 are diagrams for exemplarily describing a couplingstructure for accommodating elements inside a housing of the scanningmodule 110 according to embodiments of the present invention;

FIG. 35 is a diagram for exemplarily describing an internal structure ofa scanning module according to another embodiment of the presentinvention;

FIG. 36 is a diagram for exemplarily describing an internal structure ofa scanning module according to still another embodiment of the presentinvention;

FIG. 37 is a diagram for exemplarily describing a computer system inwhich embodiments described herein may be implemented;

FIG. 38 is a diagram showing the waveform of a signal before a phasedelay and the waveform of a signal after a phase delay;

FIG. 39 shows a diagram representing a phase-delayed low-resolutionimage (a), and a diagram representing a phase-corrected high-resolutionimage (b);

FIG. 40 is a diagram showing a micropattern that appears in a lightpattern in which light is emitted;

FIG. 41 is a diagram showing light and shade corresponding to a cut-offfilter and appearing in a light pattern in which light is emitted;

FIG. 42 shows a diagram representing that a non-used region occurs in anobtained image when a phase is delayed (a), and a diagram representingthat a non-used region occurs at a corner in an obtained image when aphase is corrected (b);

FIG. 43 is a block diagram showing a mounting device according to anembodiment;

FIG. 44 is a diagram showing that a scanning module is accommodated inan image generating device according to an embodiment;

FIG. 45 is a diagram for describing that a scanning module is mounted ona mounting device according to an embodiment;

FIG. 46 is a sectional view showing an accommodation part of a mountingdevice according to an embodiment when viewed from the top;

FIG. 47 is a top view showing a reference pattern part according to anembodiment;

FIG. 48 is a side view showing a reference image existing on a referencepattern part according to an embodiment;

FIG. 49 is a side view showing a reference pattern part existing in aconcave structure shape according to an embodiment;

FIG. 50 shows a diagram representing that a reference pattern partdisposed below a mounting device is moved upward through an adjustmentpart according to an embodiment (a), and a diagram representing that areference pattern part disposed below a mounting device is moveddownward through an adjustment part according to an embodiment (b);

FIG. 51 is a flowchart showing that a phase is corrected using areference image existing in a mounting device according to anembodiment;

FIG. 52 is a table showing a scheme in which signals obtained by acontrol module are stored according to an embodiment;

FIG. 53 shows a table representing a scheme in which obtained signalsare stored when there is no phase delay according to an embodiment (a),and a table representing a scheme in which obtained signals are storedwhen there is a phase delay according to an embodiment (b);

FIG. 54 is a diagram for describing a method of finding a differencebetween signal values obtained at prediction times along a light patternaccording to an embodiment;

FIG. 55 is a flowchart for describing that a phase is corrected using adifference between values obtained at prediction times along a lightpattern according to an embodiment;

FIG. 56 is a flowchart for describing that a phase is corrected using avalue acquired for a pixel of an image obtained by a control moduleaccording to an embodiment;

FIG. 57 is a diagram showing standard deviation informationcorresponding to a phase change according to an embodiment;

FIG. 58 is a diagram for describing a method of finding a value ofminimizing standard deviation information along a trajectory accordingto an embodiment;

FIG. 59 is a diagram for describing a method of finding a value ofminimizing standard deviation information within a limited rangeaccording to an embodiment;

FIG. 60 is a diagram for describing a local minimal value when a minimalvalue of standard deviation information is found using a trajectoryaccording to an embodiment;

FIG. 61 is a diagram for describing a change in a fill factor (FF) alongwith a phase change according to an embodiment;

FIG. 62 is a flowchart showing that discovery is performed along atrajectory to discover a phase in which standard deviation informationis smallest according to an embodiment;

FIG. 63 is a diagram for describing a method of finding a phase ofminimizing standard deviation information along a trajectory accordingto an embodiment;

FIG. 64 is a diagram for describing a method of finding a phase ofminimizing standard deviation information along a trajectory accordingto an embodiment;

FIG. 65 is a flowchart for describing a method of discovering a phase inwhich standard deviation information is smallest within a limited rangeafter discovery is made along a trajectory according to an embodiment;

FIG. 66 is a flowchart for describing a method of discovering a phase inwhich standard deviation information is smallest within a shortenedphase discovery unit after phase discovery is made along a trajectory inorder to perform a phase calibration according to an embodiment;

FIG. 67 is a diagram for describing a change in an FF along with a phasedifference between driving signals according to an embodiment;

FIG. 68 is a diagram for describing a change in an FF along with a phasedifference between driving signals according to an embodiment;

FIG. 69 is a flowchart for describing that an image having a high FF isobtained by adjusting the phase of a driving signal according to anembodiment;

FIG. 70 is a diagram for describing that a light path is changed bychanging the phase of a driving signal according to an embodiment;

FIG. 71 is a diagram for describing that a position where a lightpattern passes is overlapping while the phase of a driving signal isbeing changed according to an embodiment;

FIG. 72 is a flowchart for describing that one image is generated usingobtained values while the phase of a driving signal is being changedaccording to an embodiment; and

FIG. 73 is a flowchart for describing that one image is generated usingobtained values while the phase of a driving signal is being changed tohave a predetermined FF according to an embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The above aspects, features, and advantages of the present inventionwill become more apparent from the following detailed description takenin conjunction with the accompanying drawings. Since the presentinvention may be variously modified and have several exemplaryembodiments, specific embodiments will be shown in the accompanyingdrawings and described in detail.

In the drawings, the thickness of layers and regions is exaggerated forclarity. Also, when it is mentioned that an element or layer is “on”another element or layer, the element or layer may be formed directly onanother element or layer, or a third element or layer may be interposedtherebetween. Like reference numerals refer to like elements throughoutthe specification. Further, like reference numerals will be used todesignate like elements having similar functions throughout the drawingswithin the scope of the present invention.

Detailed descriptions about well-known functions or configurationsassociated with the present invention will be ruled out in order not tounnecessarily obscure subject matters of the present invention. Itshould also be noted that, although ordinal numbers (such as first andsecond) are used in the following description, they are used only todistinguish similar elements.

The suffixes “module” and “unit” for elements used in the followingdescription are given or used interchangeably only for facilitation ofpreparing this specification, and thus they are not assigned a specificmeaning or function.

According to an embodiment, there may be provided an optical deviceincluding an optical fiber having a fixed end and a free end; a firstactuator positioned at a actuator position between the fixed end and thefree end and configured to apply a first force on the actuator positionof the optical fiber such that a movement of the free end of the opticalfiber in a first direction is caused, wherein the first direction isorthogonal to a longitudinal axis of the optical fiber; and a deformablerod disposed adjacent to the optical fiber, and having a first end and asecond end, wherein the first end is connected to a first rod positionof the optical fiber and the second end is connected to a second rodposition of the optical fiber, wherein the first rod position and thesecond rod position of the optical fiber are positioned between theactuator position and the free end, wherein the deformable rod issubstantially parallel to the optical fiber from the first rod positionof the optical fiber to the second rod position of the optical fiber,and wherein, in the cross section perpendicular to the longitudinal axisof the optical fiber, the deformable rod is arranged such that an anglebetween a virtual line connected from the first end of the deformablerod to the first rod position of the optical fiber and the firstdirection is within a predetermined angle, whereby the movement of theoptical fiber in a second direction perpendicular to the first directionis limited when the free end of the optical fiber moves in the firstdirection as the first actuator applies the first force on the actuatorposition of the optical fiber. Also, the optical device may furtherinclude a second actuator configured to apply a second force on theactuator position of the optical fiber, wherein the second actuatorinduce the free end of the optical moves in the second direction.

Also, the optical fiber may vibrate by the first force applied from thefirst actuator and the second force applied from the second actuator andmoves corresponding to a Lissagjous pattern in accordance with apredetermined condition.

Also, the optical fiber may have a first rigidity and the deformable rodhas a second rigidity.

Also, the deformable rod may change the rigidity of the optical fiberfor at least one of the first direction and the second direction whenthe optical fiber moves in accordance with the first force and thesecond force.

Also, the optical fiber may drive different resonant frequencies withrespect to the first direction and the second direction.

Also, a length of the deformable rod may be shorter than a length of theoptical fiber.

Also, the first end of the deformable rod may be fixed to the first rodposition of the optical fiber by a first connector and the second end ofthe deformable rod is fixed to the second rod position of the opticalfiber by a second connector.

Also, the first connector and the second connector may move as theoptical fiber vibrates.

Also, the optical device may further include a controller configured toapply a first driving frequency to the first actuator and a seconddriving frequency to the second actuator.

Also, a difference between the first driving frequency and the seconddriving may be more than a predetermined range.

Also, the predetermined angle may be below +a ° and −b ° about the firstdirection.

Also, the a ° and b ° may have different values.

Also, an absolute value of a minus b (|a−b|) may be below 10 about thefirst direction.

Also, an absolute value of a minus b (|a−b|) may be below 5 about thefirst direction.

According to another aspect, there may be provided an optical deviceincluding an optical fiber having a fixed end and a free end, andconfigured to irradiate a predetermined scanning pattern; a firstactuator positioned at a actuator position between the fixed end and thefree end and configured to apply a first force on the actuator positionof the optical fiber such that a movement of the free end of the opticalfiber in a first direction is caused; a second actuator configured toapply a second force on the actuator position of the optical fiber suchthat a movement of the free end of the optical fiber in a seconddirection is caused, wherein the first direction is orthogonal to alongitudinal axis of the optical fiber, and the second direction isperpendicular to the first direction; a deformable rod having a firstend and a second end, and disposed in the first direction or the seconddirection adjacent to the optical fiber, wherein the first end is fixedto a first rod position of the optical fiber and the second end is fixedto a second rod position of the optical fiber, wherein the first rodposition and the second rod position of the optical fiber are positionedbetween the actuator position and the free end; and a controllerconfigured to apply a first driving frequency to the first actuator anda second driving frequency to the second actuator; wherein an aspectratio of the scanning pattern irradiated by the optical fiber isassociated with the attachment direction of the deformable rod, andwherein the controller adjusts the aspect ratio of the scanning patternby applying a first voltage to the first actuator and a second voltageto the second actuator.

Also, the first driving frequency and the second driving frequency maybe different.

Also, the controller may apply the same voltage to the first actuatorand the second actuator so that the optical fiber irradiates thescanning pattern having a different aspect ratio with respect to thefirst direction and the second direction.

Also, the aspect ratio of the first direction may be greater than thesecond direction when the deformable rod is fixed on the firstdirection.

Also, the aspect ratio of the second direction may be greater than thefirst direction when the deformable rod is fixed on the seconddirection.

Also, the controller may apply a voltage greater than the secondactuator to the first actuator to irradiate the scanning pattern havinga one-to-one ratio with respect to the first direction and the seconddirection.

Also, the controller may control the optical fiber so as to movecorresponding a Lissajous pattern in accordance with a predeterminedcondition.

Also, a difference between the first driving frequency and the seconddriving may be more than a predetermined range.

Also, the first end of the deformable rod may be fixed to the first rodposition of the optical fiber by a first connector and the second end ofthe deformable rod is fixed to the second rod position of the opticalfiber by a second connector.

Also, the first connector and the second connector may move together asthe optical fiber vibrates.

Also, in the cross section perpendicular to the longitudinal axis of theoptical fiber, the deformable rod may be arranged such that an anglebetween a virtual line connected from the first end of the deformablerod to the first rod position of the optical fiber and the firstdirection is within a predetermined angle.

Also, the predetermined angle may be below +a ° and −b ° about the firstdirection.

Also, the a ° and b ° may have different values.

Also, an absolute value of a minus b (|a−b|) may be below 10 about thefirst direction.

Also, an absolute value of a minus b (|a−b|) may be below 5 about thefirst direction.

Also, the optical fiber has a first rigidity and the deformable rod mayhave a second rigidity.

Also, the deformable rod may change the rigidity of at least one of thefirst direction and the second direction of the optical fiber when theoptical fiber moves in accordance with the first force and the secondforce.

According to another aspect, there may be provided an image generatingdevice including an irradiation unit configured to irradiate light to anobject, a light receiving unit configured to receive the returned lightfrom the object and obtain a signal based on the returned light, and acontroller configured to generate an image based on the signal obtainedfrom the light receiving unit, the device comprising: an optical fiberhaving a fixed end and a free end; a first actuator positioned at aactuator position between the fixed end and the free end and configuredto apply a first force on the actuator position of the optical fibersuch that a movement of the free end of the optical fiber in a firstdirection is caused; a second actuator configured to apply a secondforce on the actuator position of the optical fiber such that a movementof the free end of the optical fiber in a second direction is caused,wherein the first direction is orthogonal to a longitudinal axis of theoptical fiber, and the second direction is perpendicular to the firstdirection; a deformable rod having a first end and a second end, anddisposed in the first direction or the second direction adjacent to theoptical fiber, wherein the first end is fixed to a first rod position ofthe optical fiber and the second end is fixed to a second rod positionof the optical fiber, wherein the first rod position and the second rodposition of the optical fiber are positioned between the actuatorposition and the free end, wherein an aspect ratio of the generatedimage is associated with the attachment direction of the deformable rod,and wherein the controller adjusts the aspect ratio of the generatedimage by applying a first voltage to the first actuator and a secondvoltage to the second actuator. According to another aspect, there maybe provided an optical device including an optical fiber having a fixedend and a free end; a first actuator positioned at a actuator positionbetween the fixed end and the free end and configured to apply a firstforce on the actuator position of the optical fiber such that a movementof the free end of the optical fiber in a first direction is caused; asecond actuator configured to apply a second force on the actuatorposition of the optical fiber such that a movement of the free end ofthe optical fiber in a second direction, wherein the first direction isorthogonal to a longitudinal axis of the optical fiber, and the seconddirection is perpendicular to the first direction; a mass having apreselected size, and disposed between the fixed end and the free end ofthe optical fiber; and a housing receiving the optical fiber, the firstactuator and the second actuator, wherein the optical fiber vibratesinside the housing by the first force and the second force, and amaximum movement range of the optical fiber depends on the location ofthe mass, wherein the mass is located away from the free end of theoptical fiber by a buffer distance to prevent the mass from collidingwith an inner wall of the housing and being damaged when the opticalfiber vibrates, and wherein the buffer distance is set based on at leastone of the size of the mass, an inner diameter of the housing, and themaximum movement range of the optical fiber, and wherein the bufferdistance is determined at least one of the following is less than ½ ofan inner diameter of the housing: the maximum movement range of theoptical fiber from the center of the inner diameter and a maximummovement range of the mass from the center of the inner diameter.

Also, the buffer distance may be at least equal to or greater than alength of the mass.

Also, the optical device may further include a deformable rod disposedadjacent to the optical fiber, and having a first end and a second end,wherein the first end is fixed to a first rod position of the opticalfiber and the second end is fixed to a second rod position of theoptical fiber, wherein the first rod position and the second rodposition of the optical fiber are positioned between the actuatorposition and the free end, wherein the deformable rod is substantiallyparallel to the optical fiber from the first rod position of the opticalfiber to the second rod position of the optical fiber.

Also, in the cross section perpendicular to the longitudinal axis of theoptical fiber, the deformable rod may be arranged such that an anglebetween a virtual line connected from the first end of the deformablerod to the first rod position of the optical fiber and the firstdirection is within a predetermined angle.

Also, the optical fiber may vibrate by the first force applied from thefirst actuator and the second force applied from the second actuator andmove corresponding to a Lissagjous pattern in accordance with apredetermined condition.

Also, the first end of the deformable rod may be fixed to the first rodposition of the optical fiber by a first connector and the second end ofthe deformable rod is fixed to the second rod position of the opticalfiber by a second connector.

Also, the optical device may further include a controller configured toapply a first driving frequency to the first actuator and a seconddriving frequency to the second actuator.

Also, a difference between the first driving frequency and the seconddriving may be more than a predetermined range.

Also, the size of the mass may be preselected so that the optical fiberis resonantly driven with a predetermined amplitude with respect to thefirst direction and the second direction.

Also, the mass may be attached to the second rod position to fix thesecond end of the deformable rod on the optical fiber.

Also, the second rod position may be determined such that the opticalfiber has a different resonant frequency with respect to the firstdirection and the second direction.

According to another aspect, there may be provided an image generatingdevice for obtaining an image of an object, including a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set based on the first signal, the second signal andthe light receiving signal, wherein the control module configured toobtain a second data set based on the first data set by adjusting atleast one of the first phase component of the first signal and thesecond phase component of the second signal, wherein the control moduleconfigured to select from the first data set and the second data setbased on predetermined criteria, and wherein the image of the object isgenerated based on the selected data set. Also, the light receivingsignal may include a light intensity corresponding to a plurality ofpixel positions determined by the first signal and the second signal.

Also, the light intensity corresponding to at least one of the pixelpositions may be plural, and the control module may be configured toselect a data set among the first data set and the second data set basedon a difference among the plurality of light intensities correspondingto each of the pixel positions in the first data set and the second dataset.

Also, the control module may select the data set among the first dataset and the second data set for obtaining the image of the object, andthe selected data set may have the smallest sum of the difference amongthe plurality of light intensities corresponding to each of pixelpositions.

Also, the difference among the plurality of light intensities maycomprise a variance among the plurality of light intensities.

Also, the difference among the plurality of light intensities may be astandard deviation among the plurality of light intensities.

Also, at least one of the light intensities corresponding to a firstpixel position in the second data set may be different from at least oneof the light intensities corresponding to the first pixel position inthe first data set.

Also, the first data set may be generated using the first signal, thesecond signal and the light receiving signal, and the second data setmay be generated using a phase-adjusted first signal, the second signaland the light receiving signal when the first phase component of thefirst signal is adjusted.

Also, the first data set may be generated using the first signal, thesecond signal and the light receiving signal, and the second data setmay be generated using the first signal, a phase-adjusted second signaland the light receiving signal when the second phase component of thesecond signal is adjusted.

Also, the first data set may be generated using a signal that at leastone phase components of the first signal and the second signal isadjusted and the light receiving signal, and the second data set may begenerated using a signal that at least one phase components of the firstsignal and the second signal is adjusted and the light receiving signal.

Also, the light intensity of the light receiving signal corresponding tothe plurality of pixel positions of the second data set may be shiftedfrom the first data set.

Also, the first axis direction may be perpendicular to the second axisdirection, and the first axis direction may represent x-axis of arectangular coordinate system and the second axis direction mayrepresent y-axis of the rectangular coordinate system.

Also, the first phase component of the first signal may be adjusted,wherein the first signal which phase not adjusted may be applied to theemitting unit, and the phase-adjusted first signal may be used forgenerating the phase-adjusted data set.

Also, the emitting unit may emit the light in a predetermined pattern asthe first signal and the second signal are applied.

Also, the control module may determine the adjusted phase componentwhich is corresponding to the image generated by using thephase-adjusted data set as a final adjustment phase for adjusting atleast one of the first signal and the second signal.

According to another aspect, there may be provided an image generatingmethod for obtaining an image of an object, including: generating afirst signal having a first frequency component and a first phasecomponent for a first axis direction, and a second signal having asecond frequency component and a second phase component in a second axisdirection through a control module; obtaining light receiving signalbased on returned light from the object, through a light receiving unit;obtaining a first data set based on the first signal, the second signaland the light receiving signal, obtaining a second data set based on thefirst data set by adjusting at least one of the first phase component ofthe first signal and the second phase component of the second signal,selecting from the first data set and the second data set based onpredetermined criteria, and generating the image of the object based onthe selected data set.

According to another aspect, there may be provided a non-transitorycomputer-readable recording medium having recorded thereon one or moreprograms comprising commands for executing the image generating method.

According to another aspect, there may be provided an image generatingdevice for obtaining an image of an object including a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set based on the first signal, the second signal andthe light receiving signal, wherein the control module configured toobtain a second data set based on the first data set by adjusting atleast one of the first phase component of the first signal and thesecond phase component of the second signal using a first amount ofphase adjustment, wherein the control module configured to select fromthe first data set and the second data set based on predeterminedcriterion, wherein the control module configured to obtain a third dataset based on the second data set by adjusting phase component of atleast one of signals used for obtaining the second data set using thefirst amount of phase adjustment, when the second data set is selectedamong the first data set and the second data set, wherein the controlmodule configured to select from the second data set and the third dataset based on the predetermined criterion, and wherein the control moduleconfigured to generate the image of the object based on the second dataset, when the second data set is selected among the second data set andthe third data set.

Also, the first amount of phase adjustment may be set to correspond afill factor according to signals corresponding to the first data set anda fill factor according to signals corresponding to the second data set,wherein the fill factors represents a degree of inclusion of a lightemission region from the image generating device in a predeterminedplurality regions.

Also, the control module may be configured to obtain at least one of acandidate phase based on phase component of signals corresponding to thesecond data set for generating the image of the object, wherein thecontrol module may be configured to obtain at least one of a candidatedata set corresponding to at least one of the candidate phase, whereinthe control module may be configured to select a first candidate dataset mostly corresponding to the predetermined criterion among the atleast one of the candidate data set, and wherein the control moduleconfigured to generate the image of the object based on the firstcandidate data set.

Also, the control module may be configured to obtain a fourth data setbased on the second data set by adjusting at least one of signals usedfor obtaining the second data set using a second amount of phaseadjustment, wherein the control module may be configured to select fromthe second data set and the fourth data set based on the predeterminedcriterion, wherein the control module may be configured to obtain afifth data set based on the fourth data set by adjusting at least one ofsignals used for obtaining the fourth data set using the second amountof phase adjustment, when the fourth data set is selected among thesecond data set and the fourth data set, wherein the control module maybe configured to select from the fourth data set and the fifth data setbased on the predetermined criterion, and wherein the control module maybe configured to generate the image of the object based on the fourthdata set, when the second data set is selected among the fourth data setand the fifth data set.

Also, the signals corresponding to the first data set may include asignal substantially 90 degree changed from a first phase anglecomponent of the first signal and a signal substantially 90 degreechanged from a second phase angle component of the second signal,wherein the first phase angle component is based on the first frequencycomponent and the first phase component, and the second phase anglecomponent is based on the second frequency component and the secondphase component.

Also, the control module may compare the first frequency component andthe second frequency component, wherein the control module may beconfigured to adjust a phase component of signal having the firstfrequency component among the signals corresponding to the first dataset by the first amount of phase adjustment, when the first frequencycomponent is smaller than the second frequency component, and whereinthe control module may be configured to adjust a phase component ofsignal having the second frequency component among the signalscorresponding to the first data set by the first amount of phaseadjustment, when the second frequency component is smaller than thefirst frequency component.

Also, first data set may include a first pixel position and a secondpixel position, wherein the light receiving signal includes lightintensities corresponding to of the first pixel position and lightintensities corresponding to the second pixel position, wherein thesecond data set may include a third pixel position and a fourth pixelposition, wherein the light receiving signal may include lightintensities corresponding to the third pixel position and lightintensities corresponding to the fourth pixel position, wherein thecontrol module may be configured to obtain a first sum representing asum of a difference value of the light intensities corresponding to thefirst pixel position and a difference value of the light intensitiescorresponding to the second pixel position, wherein the control modulemay be configured to obtain a second sum representing a sum of adifference value of the light intensities corresponding to the thirdpixel position and a difference value of the light intensitiescorresponding to the fourth pixel position, and wherein the controlmodule may be configured to determine the second data set is morecorresponding to the predetermined criterion than the first data set,when the second sum is smaller than the first sum.

Also, the difference value of the light intensities corresponding to thepixel positions may be a standard deviation of the light intensitiescorresponding to the pixel positions.

Also, the control module may be configured to obtain a difference valueamong the phase component of the signals corresponding to the seconddata set, wherein the control module may be configured to adjust atleast one of phase component among the first signal and the secondsignal using the difference value among the phase component and apredetermined phase adjustment value, and wherein the emitting unit maybe configured to emit light to the object by receiving the signal atleast one of the phase component among the first signal and the secondsignal using the difference value among the phase component and thepredetermined phase adjustment value.

Also, the predetermined phase adjustment value may be determined basedon substantially half of an odd multiple of the first amount of phaseadjustment and the first amount of phase adjustment, when the firstfrequency component and the second frequency component are odd, andwherein the predetermined phase adjustment value may be determined basedon substantially half of an even multiple of the first amount of phaseadjustment and the first amount of phase adjustment, when one of thefirst frequency component and the second frequency component is even.

According to another aspect, there may be provided an image generatingdevice for obtaining an image of an object, including a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first data set using the first signal, the second signal andthe light receiving signal, wherein the control module adjusts a phasecomponent of at least one of the first signal or the second signal by afirst amount of phase adjustment by plurality of times, wherein thecontrol module configured to obtain a plurality of data sets using eachof the signal adjusted by the plurality of times and a light receivingsignal adjusted by the plurality of times, wherein the control moduleconfigured to obtain a data set using at least one of the signal and thelight receiving signal, when each time at least one of the signal isadjusted by the first amount of phase adjustment, wherein the controlmodule configured to obtain a nth data set using at least one of thesignal which the phase component is adjusted by the first amount ofphase adjustment n times and the light receiving signal, when at leastone of the signal is adjusted by the first amount of phase adjustment ntimes, wherein the control module adjusts a phase component of at leastone of the first signal or the second signal by the first amount ofphase adjustment by (n+1) times, when the nth data set is morecorresponding to the predetermined criterion than a (n−1)th data setobtained previously than the nth data set, wherein the (n−1)th data setis obtained when the phase component of at least one of the first signaland the second signal is adjusted by the first amount of phaseadjustment (n−1) times, wherein the control module configured to obtaina (n+1)th data set using at least one of the signal which the phasecomponent is adjusted by the first amount of phase adjustment by (n+1)times and the light receiving signal, and wherein the control moduleproducing the image based on at least one of the signal which the phasecomponent is adjusted by the first amount of phase adjustment (n−1)times, when the (n−1)th data set is more corresponding to thepredetermined criterion than the nth data set.

Also, at least one of the signal adjusted by the first amount of phaseadjustment may be the first signal having the first frequency componentand the first phase component, wherein the control module may beconfigured to obtain a mth data set using a second signal which thephase component is adjusted by the first amount of phase adjustment mtimes and the light receiving signal, when the second phase component ofthe second signal is adjusted by the first amount of phase adjustment bym times, wherein the m is an integer larger than 2, wherein the controlmodule may adjust a phase component of at least one of the first signalor the second signal by the first amount of phase adjustment (m+1)times, when the mth data set is more corresponding to the predeterminedcriterion than a (m−1)th data set obtained previously than the mth dataset, wherein the (m−1)th data set may be obtained when the phasecomponent of the second signal is adjusted by the first amount of phaseadjustment (m−1) times, wherein the control module may be configured toobtain a (m+1)th data set using at least one of the signal which thephase component is adjusted by the first amount of phase adjustment(m+1) times and the light receiving signal, wherein the control moduleproducing the image based on the second signal which the phase componentmay be adjusted by the first amount of phase adjustment (m−1) times,when the (m−1)th data set is more corresponding to the predeterminedcriterion than the mth data set.

Also, the data set of any one of the obtained data sets may include aplurality of first pixel position and a plurality of second pixelposition, wherein the light receiving signal of the any one of the dataset may include light intensities corresponding to the first pixelposition and light intensities corresponding to the second pixelposition, wherein the other data set which excepts the any one of thedata set among the obtained data sets may include a third pixel positionand a fourth pixel position, wherein the light receiving signal mayinclude light intensities corresponding to the third pixel position andlight intensities corresponding to the fourth pixel position, whereinthe control module may be configured to obtain a first sum representinga sum of a difference value of the light intensities corresponding tothe first pixel position and a difference value of the light intensitiescorresponding to the second pixel position, wherein the control modulemay be configured to obtain a second sum representing a sum of adifference value of the light intensities corresponding to the thirdpixel position and a difference value of the light intensitiescorresponding to the fourth pixel position, and wherein the controlmodule determines the second data set may be more corresponding to thepredetermined criterion than the first data set, when the second sum issmaller than the first sum.

Also, the difference value of the light intensities corresponding to thepixel position is a standard deviation of the light intensitiescorresponding to the pixel position.

According to another aspect, there may be provided an image generatingdevice for obtaining an image of an object, including a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured toobtain a first phase adjusted signal which is a sum of a n times of afirst amount of phase adjustment and the first phase component of thefirst signal, wherein the control module configured to obtain a secondphase adjusted signal which is a sum of a m times of a first amount ofphase adjustment and the second phase component of the second signal,wherein the n and m are different integer and larger than 1, and whereinthe control module configured to generate the image using a first dataset obtained based on the first phase adjusted signal, when the firstdata set obtained based on the first phase adjusted signal and thesecond signal is more corresponding to a predetermined criterion than asecond data set obtained based on the second phase adjusted signal andthe second signal.

Also, the data set of any one of the obtained data sets may include afirst pixel position and a second pixel position, wherein the lightreceiving signal of the any one of the data set includes lightintensities corresponding to the first pixel position and lightintensities corresponding to the second pixel position, wherein theother data set which excepts the any one of the data set among theobtained data sets may include a third pixel position and a fourth pixelposition, wherein the light receiving signal may include lightintensities corresponding to the third pixel position and lightintensities corresponding to the fourth pixel position, wherein thecontrol module may be configured to obtain a first sum representing asum of a difference value of the light intensities corresponding to thefirst pixel position and a difference value of the light intensitiescorresponding to the second pixel position, wherein the control modulemay be configured to obtain a second sum representing a sum of adifference value of the light intensities corresponding to the thirdpixel position and a difference value of the light intensitiescorresponding to the fourth pixel position, and wherein the controlmodule may determine the second data set is more corresponding to thepredetermined criterion than the first data set, when the second sum issmaller than the first sum.

Also, the difference value of the light intensities corresponding to thepixel position is a standard deviation of the light intensitiescorresponding to the pixel position.

According to another aspect, there may be provided an image generatingdevice for obtaining an image of an object, including a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module configured togenerate and output a first image using the first signal and the secondsignal at a first point of time, wherein at least one of the firstsignal and the second signal is adjusted during a predetermined timeperiod after the first point of time, wherein the control modulegenerates and outputs a second image using at least one of the phaseadjusted signal at a second point of time after the predetermined timeperiod, wherein a difference between the phase of the first signal atthe first point of time and the phase of the first signal at the secondpoint of time and a difference between the phase of the second signal atthe first point of time and the phase of the second signal at the secondpoint of time are different by substantially an integer multiple of afirst amount of phase adjustment, and wherein the first amount of phaseadjustment is determined based on the first frequency component and thesecond frequency component.

According to another aspect, there may be provided an image generatingmethod for obtaining an image of an object, including generating a firstsignal having a first frequency component and a first phase componentfor a first axis direction, and a second signal having a secondfrequency component and a second phase component in a second axisdirection through a control module; obtaining light receiving signalbased on returned light from the object, through a light receiving unit;obtaining a first data set based on the first signal, the second signaland the light receiving signal; obtaining a second data set based on thefirst data set by adjusting at least one of the first phase component ofthe first signal and the second phase component of the second signalusing a first amount of phase adjustment; selecting from the first dataset and the second data set based on predetermined criterion; obtaininga third data set based on the second data set by adjusting phasecomponent of at least one of signals used for obtaining the second dataset using the first amount of phase adjustment, when the second data setis selected among the first data set and the second data set; selectingfrom the second data set and the third data set based on thepredetermined criterion; and generating the image of the object based onthe second data set, when the second data set is selected among thesecond data set and the third data set.

According to another aspect, there may be provided a non-transitorycomputer-readable recording medium having recorded thereon one or moreprograms comprising commands for executing the image generating method.

According to another aspect, there may be provided a light irradiatingunit, comprising: a control module configured to generate a first signalhaving a first frequency component and a first phase component for afirst axis direction, and a second signal having a second frequencycomponent and a second phase component for a second axis direction; anemitting unit configured to emit light to the object using the firstsignal and the second signal; and a light receiving unit configured toobtain light receiving signal based on returned light from the object;wherein the control module configured to obtain a first data set basedon the first signal, the second signal and the light receiving signal,wherein the control module configured to obtain a second data set basedon the first data set by adjusting at least one of the first phasecomponent of the first signal and the second phase component of thesecond signal using a first amount of phase adjustment, wherein thecontrol module configured to select from the first data set and thesecond data set based on predetermined criterion, wherein the controlmodule configured to obtain a third data set based on the second dataset by adjusting phase component of at least one of signals used forobtaining the second data set using the first amount of phaseadjustment, when the second data set is selected among the first dataset and the second data set, wherein the control module configured toselect from the second data set and the third data set based on thepredetermined criterion, and wherein the control module configured togenerate the image of the object based on the second data set, when thesecond data set is selected among the second data set and the third dataset.

According to another aspect, there may be provided an optical device foremitting light to an object, comprising: a control module configured togenerate actuating signals; and an emission unit configured to receivethe actuating signals and emit light to the object based on theactuating signals; wherein when the emission unit receives a firstactuating signal having a first actuating frequency and a first phaseand a second actuating signal having a second actuating frequency and asecond phase among the actuating signals, the emission unit emits thelight with a first scanning pattern based on the first actuating signaland the second actuating signal, wherein when the emission unit receivesa third actuating signal having the third actuating frequency and athird phase and a fourth actuating signal having a fourth actuatingfrequency and a fourth phase among the actuating signals, the emissionunit emits the light with a second scanning pattern based on the thirdactuating signal and the fourth actuating signal, wherein the firstphase and the second phase have different by a first phase difference,wherein the third phase and the fourth phase have different by a secondphase difference, and wherein the control module configured to generatethe actuating signals by setting difference between the first phasedifference and the second phase difference being n times of apredetermined phase.

Also, the optical device may further include a light receiving unitconfigured to receive light returning from the object and generate lightreceiving signal, for obtaining light returning from the object andobtaining an image of the object using the obtained light; wherein thecontrol module is configured to obtain a first data set using lightreturned from the object with the first scanning pattern, wherein thecontrol module is configured to obtain a second data set using lightreturned from the object with the second scanning pattern, and whereinthe control module is configured to obtain a third data set using thefirst data set and the second data set and generates the image of theobject based on the third data set.

Also, a plurality of regions may be defined from the third data set, andwherein a first fill factor representing a degree of inclusion of theplurality of regions from the third data set in a predetermined totalregions of the image of the object may be larger than a predeterminedcriterion.

Also, the first fill factor is 100%.

Also, the predetermined phase may be based on the first actuatingfrequency or the second actuating frequency and a predetermined totalregions when light is emitted from the optical device, when the phasedifference between the first phase and the second phase and the phasedifference between the third phase and the fourth phase are differed byn times of a predetermined phase.

Also, the predetermined phase is determined by a first formula

$\begin{matrix}{a = {\frac{1}{2\pi \; f_{x}}{\sin^{- 1}\left( \frac{2}{pixel} \right)}}} & \left\lbrack {{The}\mspace{14mu} {first}\mspace{14mu} {Formula}} \right\rbrack\end{matrix}$

where a indicates the predetermined phase, f_(x) indicates the firstdriving frequency, and pixel indicates the number of predeterminedregions.

Also, the predetermined phase may be determined by a second Formula

$\begin{matrix}{a = {\frac{1}{2\pi \; f_{y}}{\sin^{- 1}\left( \frac{2}{pixel} \right)}}} & \left\lbrack {{The}\mspace{14mu} {second}\mspace{14mu} {Formula}} \right\rbrack\end{matrix}$

where a indicates the predetermined phase, f_(y) indicates the seconddriving frequency, and pixel indicates the number of predeterminedregions.

Also, the n may be obtained based on the first actuating frequency orthe second actuating frequency, a greatest common denominator of thefirst actuating frequency and the second actuating frequency and apredetermined total regions, when the phase difference between the firstphase and the second phase and the phase difference between the thirdphase and the fourth phase, by n times of a predetermined phase.

Also, n may be determined by a third Formula

$\begin{matrix}{n = \frac{{GCD}*\pi}{f_{x}*{\sin^{- 1}\left( \frac{2}{pixel} \right)}}} & \left\lbrack {{The}\mspace{14mu} {third}\mspace{14mu} {Formula}} \right\rbrack\end{matrix}$

where GCD indicates the greatest common divisor between the firstdriving frequency and the second driving frequency, f_(x) indicates thefirst driving frequency, and pixel indicates the number of predeterminedregions.

Also, n may be determined by a forth Formula

$\begin{matrix}{n = \frac{{GCD}*\pi}{f_{y}*{\sin^{- 1}\left( \frac{2}{pixel} \right)}}} & \left\lbrack {{The}\mspace{14mu} {fourth}\mspace{14mu} {Formula}} \right\rbrack\end{matrix}$

where GCD indicates the greatest common divisor between the firstdriving frequency and the second driving frequency, f_(y) indicates thesecond driving frequency, and pixel indicates the number ofpredetermined regions.

According to another aspect, there may be provided an light emittingmethod by an optical device for emitting light to an object, wherein theoptical device comprising a control module configured to generateactuating signals and an emission unit configured to receive theactuating signals and emit light to the object based on the actuatingsignals, the light emitting method comprising: receiving a firstactuating signal having a first actuating frequency and a first phaseand a second actuating signal having a second actuating frequency and asecond phase among the actuating signals, the emission unit emits thelight with a first scanning pattern based on the first actuating signaland the second actuating signal, through the emission unit; andreceiving a third actuating signal having the third actuating frequencyand a third phase and a fourth actuating signal having a fourthactuating frequency and a fourth phase among the actuating signals, theemission unit emits the light with a second scanning pattern based onthe third actuating signal and the fourth actuating signal, through theemission unit; wherein the first phase and the second phase havedifferent by a first phase difference, wherein the third phase and thefourth phase have different by a second phase difference, wherein thecontrol module configured to generate the actuating signals by settingdifference between the first phase difference and the second phasedifference being n times of a predetermined phase. According to anotheraspect, there may be provided a non-transitory computer-readablerecording medium having recorded thereon one or more programs comprisingcommands for executing the light emitting method.

According to another aspect, there may be provided a mounting device formounting an image generating device including a probe, emitting light toan object from an one end of the probe and receiving light returningfrom the object at the one end of the probe, the mounting devicecomprising: a housing configured to hold at least part of the imagegenerating device, wherein the at least part of the image generatingdevice includes the one end of the probe; and a reference imageproviding unit configured to provide at least one of a reference imagesuch that the image generating device performs a phase adjustment of anactuating signal related to positions of the emitted light on the objectfrom the one end of the probe when the housing holds the at least partof the image generating device; wherein the reference image providingunit adjusts a position of the reference image for corresponding adistance between the one end of the probe and the reference image to afocal length of the probe.

According to another aspect, there may be provided a mounting device formounting an image generating device comprising a probe, emitting lightto an object from an one end of the probe and receiving light returningfrom the object at the one end of the probe, including a housingconfigured to hold at least a part of the image generating device,wherein at least the part of the image generating device includes theone end of the probe; and a reference image providing unit configured toprovide a plurality of a reference image for performing a phaseadjustment of an actuating signal which determines a position of lightemission on the object from the one end, when the housing holds at leastof the part of the image generating device; wherein the reference imageproviding unit comprises a plurality of layers including each of theplurality of reference image for corresponding a distance between theone end of the probe and the reference image to a focal length of theprobe.

Also, the mounting device may further include an adjusting unitconfigured to adjust the position of the reference image forcorresponding the distance between the one end of the probe and thereference image to the focal length of the probe.

Also, the reference image may be configured to use a reflective materialfor using a reflected signal when the image generating device emitslight.

Also, the reference image providing unit may further include a cartridgeconfigured to provide a fluorescent material to the reference image.

Also, the cartridge may comprise at least one of fluorescent materialswhich fluoresce signal having an wavelength of 405 nm, 488 nm, 630 nmand 785 nm.

Also, the mounting device may further include a fixing unit configuredto fix the probe into the mounting device in predetermined angle.

Also, at least one layer of the reference image providing unit providesthe reference image in a transparent material.

Also, the reference image may have a circular pattern.

According to another aspect, there may be provided an Image generatingdevice for obtaining an image of an object, comprising: a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentfor a second axis direction; an emitting unit configured to emit lightto the object using the first signal and the second signal; and a lightreceiving unit configured to obtain light receiving signal based onreturned light from the object; wherein the control module performs afirst phase adjustment at least one of the first signal and the secondsignal using a light receiving signal based on light returning from areference image, when light is emitted from the emitting unit to thereference image arranged in a mounting device, at a state of theemitting unit mounted in the mounting device, wherein the mountingdevice has the reference image inside, wherein the control modulerepeatedly performs a second phase adjustment periodically using thelight receiving signal based on light returning from the referenceimage, when light is emitted from the emitting unit to the referenceimage arranged in a mounting device, at a state of the emitting unit notmounted in the mounting device, wherein the second phase adjustment isperformed based on a phase at least one of the first signal and thesecond signal adjusted by the first phase adjustment.

Also, the first phase adjustment may be the phase adjustment forcorresponding an image obtained through the control module to thereference image by comparing the image obtained by the control moduleand the reference image, wherein the image obtained by the controlmodule is based on the light receiving signal obtained from thereference image.

Also, the control module may be configured to obtain a first data setbased on the first signal, the second signal and the light receivingsignal, wherein the control module configured to obtain a second dataset based on the first data set by adjusting at least one of the firstphase component of the first signal and the second phase component ofthe second signal wherein the control module configured to select fromthe first data set and the second data set based on predeterminedcriterion, wherein the image of the object is generated based on theselected data set. wherein the first data set and the second data setincludes a plurality of pixel positions, wherein the first data set andthe second data set include light intensities corresponding to theplurality of pixel positions, wherein the predetermined criterion isdetermined by a difference between the light intensities correspondingto each of at least part of the plurality of pixel positions.

Also, the image generating device may be configured to adjust at leastone of the first signal and the second signal based on the first phaseadjustment, wherein the emitting unit is actuated until the second phaseadjustment performed.

According to another aspect, there may be provided a phase adjustingmethod by an image generating device for obtaining an image of anobject, wherein the image generating device comprising a control moduleconfigured to generate a first signal having a first frequency componentand a first phase component for a first axis direction, and a secondsignal having a second frequency component and a second phase componentin a second axis direction; an emitting unit configured to emit light tothe object using the first signal and the second signal and a lightreceiving unit configured to obtain light receiving signal by returninglight from the object, based on the light emitted by the emitting unit,the phase adjusting method including: performing a first phaseadjustment at least one of the first signal and the second signal usinga light receiving signal based on light returning from a referenceimage, when light is emitted from the emitting unit to the referenceimage arranged in a mounting device, at a state of the emitting unitmounted in the mounting device, wherein the mounting device has thereference image inside, through the control module; and repeatedlyperforming a second phase adjustment periodically using the lightreceiving signal based on light returning from the reference image, whenlight is emitted from the emitting unit to the reference image arrangedin a mounting device, at a state of the emitting unit not mounted in themounting device, through the control module; wherein the second phaseadjustment is performed based on a phase at least one of the firstsignal and the second signal adjusted by the first phase adjustment.

According to another aspect, there may be provided a non-transitorycomputer-readable recording medium having recorded thereon one or moreprograms comprising commands for executing the phase adjusting method.

1 Image Generating Device

In the following embodiment, the term “image generating device” mayrefer to an optical device for acquiring and providing at least one of areflected image RI, a fluorescence image FI, and a transmitted image TIof an object in real-time.

As an example, the image generating device may include various kinds ofendomicroscopes for directly observing or diagnosing pathologicalconditions of living bodies.

An endomicroscope is an optical microscope that is based on laser lightsuch as a confocal type, two-photon type, and OCT type.

In general, a confocal microscope uses a pinhole to block out-of-focuslight and focus only light having passed through the pinhole onto anobjective lens to perform imaging on a pixel basis.

As one microscope using this confocal principle, there is a confocallaser scanning microscope (CLSM), which applies laser light to a sample,generates light of a certain wavelength, receives only in-focus light,converts the light into a digital signal, and observes the digitalsignal.

Unlike typical optical microscopes, a confocal laser scanning microscope(CLSM) may focus a laser beam onto a sample and may generate an imageusing fluorescent light, reflected light, and transmitted light emittedfrom the sample.

For example, a fluorescence image may be observed by usingautofluorescence emitted from a specific material included in a sampleor by injecting a fluorescent material into a sample.

Also, when a confocal laser scanning microscope is used, it is possibleto obtain an image having outstanding sharpness and high resolutionbecause scattered light originating from other parts of the sample isblocked.

As another example, an image generating device may include a lasermicroscanner for precisely observing or diagnosing an object inreal-time.

Laser microscanners are typically classified into a micro electricmechanical system (MEMS) scanner using a semiconductor processing methodand an optical fiber scanner using an optical fiber.

Also, laser microscanners may be classified into a side-viewing type, acircumferential-viewing type, and a forward-viewing type.

An MEMS scanner includes a lens scanner and a mirror scanner forreflecting laser light and usually performs side imaging.

An MEMS scanner requires an additional device for re-bending a beam bentby a mirror in order to perform forward imaging, and thus is difficultto compactly package.

On the contrary, an optical fiber scanner is driven using an actuatorsuch as a piezoelectric element and thus can be simply and compactlypackaged compared to an MEMS mirror scanner.

Also, an optical fiber scanner is driven at a resonant frequency of anoptical fiber and thus implements a wide field of view (FOV) at arelatively low voltage.

The above-described image generating devices may be utilized in variousfields for acquiring a fluorescence image, a reflected image, atransmitted image, and the like of an object in the form of atwo-dimensional (2D) or three-dimensional (3D) image.

For example, the image generating devices may be used to observe anddiagnose a picture of an object in real-time in fields such asbiological research, disease diagnosis, and endoscopic surgery.

Also, for example, the image generating device may be used to measurethe remaining life of a metal structure under inspection on the basis ofcracks, holes, and the degree of creep of a metal installation.

Also, for example, the image generating device may be applied even to alight detection and ranging (LiDAR) device for generating 3D stereoinformation by reflecting and scanning a laser beam in a distributedfashion and measuring an optical return distance.

1.1 Usage Environment

FIG. 1 is a diagram for exemplarily describing an environment in whichan image generating device is used according to an embodiment of thepresent invention.

Referring to FIG. 1, an image generating device 1 according to anembodiment of the present invention may scan an object O to generate animage in real-time.

For example, the image generating device 1 may be a miniaturized opticalfiber scanner for monitoring pathological conditions of living tissue ina laboratory or an operating room in real-time.

Also, an image analysis device 2 may be a device for performing apathological diagnosis in real-time by using an image generated by theimage generating device 1.

For example, the image analysis device 2 may be an electronic deviceassigned to a medical technician capable of performing a pathologicaldiagnosis. Alternatively, for example, the image analysis device 2 maybe provided in the form of a module inside an electronic device assignedto a medical technician capable of performing a pathological diagnosis.

Also, the image generating device 1 and the image analysis device 2 maybe connected to each other over a network N.

The network N may include various wired or wireless networks, and theimage generating device 1 and the image analysis device 2 may transmitand receive various kinds of information over the network N.

For example, the image generating device 1 may transmit an imagegenerated in the image generating device 1 to the image analysis device2 over the network N in real-time.

In an embodiment, when the image analysis device 2 is provided in theform of a module in an electronic device assigned to a medicaltechnician, the image analysis device 2 may be a program and a softwareapplication for performing a pathological diagnosis on the basis of animage transmitted from the image generating device 1 in real-time.

For example, a medical technician may diagnose a cancer and determine asurgical site on the basis of a biometric image displayed on theelectronic device.

Also, for example, a medical technician may enter information related tocancer diagnosis and surgical site determination through an applicationrunning on the electronic device.

Alternatively, for example, the image analysis device 2 mayautomatically diagnose a cancer and determine a surgical site on thebasis of a prestored image analysis program.

In this case, a machine learning algorithm in which criteria for cancerdiagnosis, surgical site determination, and the like are prestored maybe stored in the image analysis device 2.

Also, for example, the image analysis device 2 may merge or mapinformation related to cancer diagnosis or surgical site determinationto an image received from the image generating device 1 and may transmitthe merging or mapping result to the image generating device 1 oranother electronic device (not shown).

The aforementioned embodiment illustrates an environment in which theimage generating device 1 is used in order to aid in understanding, andthe scope of the present invention is not limited to the above-describedembodiment.

1.2 Configuration of Image Generating Device

Schematic elements of an image generating device according to anembodiment of the present invention will be described in detail belowwith reference to FIGS. 2 to 5.

FIG. 2 is a block diagram for exemplarily describing a configuration ofan image generating device according to an embodiment of the presentinvention.

Referring to FIG. 2, an image generating device 1 according to anembodiment of the present invention may include a scanning module 110, acontroller 130, and an optical module 120.

The scanning module 110 may emit light to the object while the scanningmodule 110 is spaced a predetermined distance apart from or is incontact with an object. Accordingly, the scanning module 110 may measurethe inside of the object within a preset distance from the surface ofthe object.

For example, the preset distance may be changed by adjusting a focallength of the lens module, which will be described below, and may rangefrom 0 um to 250 um.

Also, the scanning module 110 may be a stationary device or a handheldoptical device.

For example, when the scanning module 110 is of a handheld type, thescanning module may be implemented in the form of an endoscope, a pen,or the like.

Referring to FIG. 3, according to an embodiment, the scanning module 110may be a pen-type optical device.

For example, a user may bring the optical device into direct contactwith an object to be observed or a perimeter of the object, and thescanning module 110 may measure the inside of the object up to a presetdistance from the surface of the object.

In an embodiment, the scanning module 110 may be an endoscopicmicroscope which is used in hospitals. For example, a medical technicianmay bring the scanning module 110 into contact with a patient's skinsurface, and the scanning module 110 may measure the state of epidermiscells at a depth of 50 um from the contact surface.

For example, a medical technician may bring the scanning module 110 intocontact with a patient's body part while the body part is cut open todiagnose a cancer or determine a surgical site, and the scanning module110 may measure living internal tissue at a depth of 70 um from thecontact surface.

In this case, a fluorescent dye may be pre-injected in the form of aparenteral injection in order to effectively check the pathologicalstate of the living internal tissue. In this case, the scanning module110 may emit light to the object, and the optical module 120, which willbe described below, may detect a fluorescent signal returning from theobject.

Meanwhile, the scanning module 110 may perform a scanning operationaccording to a driving signal applied from the controller 130, whichwill be described below. The principle of the scanning operationperformed by the scanning module 110 will be described in detail withreference to exemplary embodiments below.

The controller 130 may be configured to control the overall scanningoperation of the scanning module 110 such that the scanning module 110performs scanning according to a present scanning pattern.

The controller 130 may apply a preset driving signal to the scanningmodule 110.

The preset driving signal may include a frequency, a voltage, a phase,and the like.

For example, the controller 130 may adjust the frequency, voltage,phase, and the like in order to change the range of light emissionperformed by the scanning module 110.

Alternatively, the controller 130 may control the scanning module 110 toperform the scanning operation on the basis of a driving signal enteredby a user.

The preset scanning pattern may vary, and the controller 130 may apply adriving signal corresponding to the preset scanning pattern to thescanning module 110.

For example, as shown in FIG. 4, the scanning pattern may include spiralscanning, raster scanning, Lissajous scanning, and the like.

Referring to the image (a) of FIG. 4, the spiral scanning is a scanningmethod that draws a part of a spiral shape and has a lateral axis and alongitudinal axis which are implemented using the same frequency.

In the case of the spiral scanning, laser light intensity is high at thecenter, and thus a lot of signal loss and noise may be caused. Forexample, at the center, photo bleaching or photo damage may occur.

Referring to the image (b) of FIG. 4, the raster scanning is a scanningmethod performed sequentially in the horizontal direction and has alateral axis and a longitudinal axis between which there is a largefrequency difference.

In the case of the raster scanning, a relatively high voltage isrequired for a slow axis, and this may cause a reduction in frame rate.

Referring to the image (c) of FIG. 4, the Lissajous scanning is apattern generated by an intersection of two sinusoidal curvesperpendicular to each other and has a lateral axis and a longitudinalaxis implemented using different frequencies.

In the case of the Lissajous scanning, fast scanning may be implementedat a high frame rate. For example, the frame rate may be at least 10 Hz.

The optical module 120 is an optical system that applies light to thescanning module 110 and detects a returning signal through the scanningmodule 110.

According to embodiments of the present invention, the optical module120 may be a confocal microscope system, and the optical module 120 maybe separated from the scanning module 110 and provided as a separatedevice.

The optical module 120 may include at least a light-emitting unit 121and a light-receiving unit 123.

The light-emitting unit 121 may be a laser device that emits a lasersignal of a preset wavelength.

In this case, the laser device may be selected depending on which one ofa reflected image, a fluorescence image, and a transmitted image of theobject is to be observed.

For example, a laser device used in the embodiments of the presentinvention may emit a laser signal in the near-infrared region.

As an example, for fluorescent imaging, the laser signal may have awavelength of 405 nm, 488 nm, 785 nm, or the like depending on a usedfluorescent dye.

For example, the fluorescent dye may be used to distinguish pathologicalfeatures of cells, blood vessels, and tissues in a living body, and ICG,FNa, 5-ALA, or other medically approved dyes may be applied as thefluorescent dye.

Also, the light-emitting unit 121 may apply a laser source appropriatefor the scanning module 110 on the basis of a signal input from anoptical module control device (not shown).

In an embodiment, the optical module control device may control the gainof an image, the power of a laser signal emitted from the light-emittingunit 121, and the like.

For example, when the image generating device 1 according to anembodiment of the present invention is a medical optical device, thepower of the laser signal may be set to 1 mW or less.

In another embodiment, the optical module control device may be providedas a portion of the controller 130, which has been described above. Inthis case, the controller 130 may control the gain of an image, thepower of a laser signal emitted from the light-emitting unit 121, andthe like.

Also, the light-receiving unit 123 may be configured to detect a signalreturning from the object in response to light emitted from thelight-emitting unit 121 through the scanning module 110.

In this case, the signal detected by the light-receiving unit 123 may betransferred to the controller 130, which has been described above, andan image processing module 200, which will be described below.

For example, the controller 130 or the image processing module 200 mayreconstruct an image of the object on the basis of the signaltransferred from the light-receiving unit 123. The image processingoperation performed by the image processing module 200 will be describedin detail in the following relevant sections.

Optionally, the image generating device 1 may further include an inputunit 140.

For example, the input unit 140 may be an input means for selecting theoperation mode of the image generating device 1.

As an example, the operation mode may include at least a first mode anda second mode which are preset.

For example, the first mode may be a low-resolution mode or a discoverymode.

Alternatively, for example, the second mode may be a high-resolutionmode or a zoom-in mode.

Therefore, a user may select the first mode or the second mode dependingon the purpose of use and view an image of appropriate resolutionthrough a display device 300.

Also, for example, the input unit 140 may be an input means forselecting the working distance of the scanning unit 1100.

As an example, the working distance may include a first distance, asecond distance, a third distance, and the like which are preset, and aninput means corresponding to a preset working distance may beadditionally provided. The working distance may correspond to a focaldistance of a lens module, which will be described below.

For example, according to the selected working distance, the controller130 may perform the scanning operation of the scanning unit 1100 andperform a calibration operation on an image generated by the scanningunit 1100.

Meanwhile, in addition to the above-described embodiments, input meanscorresponding to various functions for controlling the operation of theimage generating device 1 may be additionally provided.

FIG. 5 is a block diagram for exemplarily describing a configuration ofthe image processing module 200 according to an embodiment of thepresent invention.

As described above with reference to FIG. 3, the image processing module200 is configured to reconstruct an image of the object on the basis ofa signal transferred from the light-receiving unit 123.

Referring to FIG. 5, the image processing module 200 may include asignal acquisition unit 210, a phase calibration unit 220, an imagereconstruction unit 230, and a data storage unit 240.

The signal acquisition unit 210 may be configured to obtain a signaldetected by the light-receiving unit 123.

The signal obtained by the signal acquisition unit 210 is a signalreturning through the scanning module after light is emitted to theobject through the scanning module 110 and may be defined as a scanningunit output signal.

For example, the signal acquisition unit 210 may additionally perform anoperation of converting an analog signal transferred from thelight-receiving unit 123 into a digital signal.

In this case, an analog-to-digital (A/D) conversion module (not shown)may be additionally provided for converting a signal received by thesignal acquisition unit 210 into a digital signal.

The phase calibration unit 220 is configured to correct a phasedifference occurring when a driving signal applied from the controller130 to the scanning module 110 is transferred to the scanning module110.

For example, in the case of an optical fiber probe driven using a forcedue to mechanical deformation of a piezoelectric element, a phasedifference with time may occur when the driving signal applied to thepiezoelectric element is transferred to the optical fiber.

For example, the scanning unit driving signal for actually driving theoptical fiber may be different from the driving signal applied to thepiezoelectric element. Accordingly, the scanning unit output signaldetected by the light-receiving unit 123 and the driving signal appliedto the piezoelectric element are caused to be different.

Therefore, during the image reconstruction process performed by theimage processing module 200, image distortion may occur by apredetermined phase difference occurring due to the difference betweenthe scanning unit output signal and the driving signal applied to thepiezoelectric element. In this case, the phase difference may be changedin real-time and may vary with a change in position of the scanningmodule 110.

In other words, in order to provide a real-time image, it may benecessary for the image generating device 1 according to an embodimentof the present invention to reconstruct the image of the object inconsideration of the phase difference varying in real-time.

As an example, a detector (not shown) for detecting the scanning unitdriving signal for actually driving the scanning module 110 may beadditionally installed inside the scanning module 110. In this case, aphase difference due to the difference between the scanning unit drivingsignal and the driving signal applied to the scanning module 110 may becalculated. Accordingly, the image processing module 200 according to anembodiment of the present invention may reconstruct the image inconsideration of the calculated phase difference.

As another example, when the optical device according to an embodimentof the present invention is provided in the form of an opticalmicroprobe, there may not be enough space inside the probe to installthe detector.

In this case, an algorithm for correcting the phase difference may beprestored in the phase calibration unit 220. The cause of the phasedifference and the phase calibration operation performed by the phasecalibration unit 220 will be described in detail in the followingrelated sections.

The image reconstruction unit 230 may be configured to reconstruct theimage of the object in consideration of a result of the phasecalibration performed by the phase calibration unit 220.

In this case, various kinds of image processing algorithms,machine-learning algorithms, and the like may be additionally providedto the image reconstruction unit 230.

For example, the image reconstruction unit 230 may additionally providefunctions for improving image quality such as noise removal,calibration, image division, image merge, and the like for a generatedimage.

Also, for example, the image reconstruction unit 230 may additionallyprovide a function of detecting a pathological feature in a generatedimage and displaying the detected pathological feature.

Also, for example, the image reconstruction unit 230 may detect apathological feature in a generated image and then additionally andautomatically perform a cancer diagnosis and a surgical sitedetermination.

The data storage unit 240 may be a memory for storing various types ofdata and may include one or more memories.

For example, an algorithm, a program, and the like related to variouskinds of functions provided by the image processing module 200 may bestored in the data storage unit 240.

As an example, a phase calibration algorithm, various image processingalgorithms for processing various kinds of image processing, a machinelearning algorithm, and the like may be stored in the data storage unit240.

Also, for example, the data storage unit 240 may store image dataobtained from the image generating device 1, image data reconstructed bythe image reconstruction unit 230, and the like.

Also, for example, an algorithm, a program, and the like related tovarious kinds of functions provided by the image processing module 200may be stored in the data storage unit 240.

As an example, a phase calibration algorithm, various image processingalgorithms for processing various kinds of image processing, a machinelearning algorithm, and the like may be stored in the data storage unit240.

In conclusion, the image processing module 200 according to anembodiment of the present invention may reconstruct a digital image ofthe object on the basis of the signal transferred from image generatingdevice 1, and the image reconstructed by the image processing module 200may be output through the display device 300 in real-time.

Also, as described above with reference to FIG. 1, the imagereconstructed by the image processing module 200 may be transmitted tothe image analysis device 2 in real-time. Accordingly, a medicaltechnician may perform a pathological feature determination anddiagnosis such as a cancer diagnosis and a surgical site determinationon the basis of the reconstructed image.

For convenience of description in the present specification, it isassumed that the image processing module 200 is provided as a separateelement in the image generating device 1, but the functions performed bythe image processing module 200 may be provided as a portion of thecontroller 130.

Alternatively, the image processing module 200 may be provided as aseparate device or a portion of another electronic device.

Alternatively, some of the functions performed by the image processingmodule 200 may be provided by the controller 130, and the otherfunctions may be provided by a separate device.

1.3 Configuration of Scanning Module

Internal elements of the scanning module 110 will be described in detailbelow with reference to FIGS. 6 to 10.

Also, for convenience of description, the following description assumesthat a handheld optical fiber probe is used to implement Lissajousscanning for an object as a main embodiment.

FIG. 6 is a block diagram for exemplarily describing an internalconfiguration of the scanning module 110 according to an embodiment ofthe present invention. FIG. 7 is a sectional view for exemplarilydescribing an internal configuration of the scanning module 110according to an embodiment of the present invention.

Referring to FIGS. 6 and 7, the scanning module 110 according to anembodiment of the present invention may include a driving unit 1101, ascanning unit 1100, and a lens module 1200.

For example, as shown in FIG. 7, the driving unit 1101, the scanningunit 1100, and the lens module 1200 of the scanning module 110 accordingto an embodiment of the present invention may be accommodated in ahousing H. In this case, the scanning unit 1100 may scan an object Oaccording to a preset scanning pattern by a force applied from thedriving unit 1101.

The housing H may have various sizes and shapes to provide a minimalspace where the scanning unit 1100 can be driven in the housing H.

For example, the housing H may be cylindrical, and the inner diameter Rof the cylindrical housing H may be designed in consideration of amaximum driving range of at least one of a first axis and a second axisof the scanning unit 1100.

Elements of the scanning module 110 accommodated in the housing H willbe described in detail below.

The driving unit 1101 may be an actuator that provides a driving forceso that the scanning unit 1100 performs a scanning operation accordingto a preset scanning pattern.

For example, the driving unit 1101 may be an actuator that is driven onthe basis of any one of a piezoelectric element, an electrostaticelement, an electromagnetic element, an electro-thermal element, a coil,and a micromotor.

An actuator based on a piezoelectric element is easy to package forfront imaging and has high durability compared to actuators based on anelectromagnetic element, an electro-thermal element, a coil, amicromotor, and the like.

A piezoelectric element is an element made of a material that generatesmechanical energy when electrical energy is applied or that generateselectrical energy when mechanical energy is applied.

For example, when an electrical signal is applied to a PZT-basedpiezoelectric material, the piezoelectric material may be deformed, andthe scanning unit 1100 may be vibrated by a force transferred from thepiezoelectric material.

Also, the piezoelectric element may be processed into various shapessuch as triangles, quadrangles, polygons, cubes, cylinders, and othersolid figures.

For example, the driving unit 1101 may use a piezoelectric elementhaving a cylindrical structure as the actuator.

In this case, the piezoelectric element may have two facingpiezoelectric electrodes driven in the first axis and the second axis.

For example, the driving unit 1101 may include a pair of first actuatingunits 1101 a driven in the first axis and a pair of second actuatingunits 1101 b driven in the second axis orthogonal to the first axis.

In this case, the first axis is a vertical axis, and the second axis isa horizontal axis orthogonal to the first axis.

In an embodiment, the controller 130 may apply driving signals to thefirst and second driving units 1101, and the first and second drivingunits 1101 may transfer a force generated according to the applieddriving signals to the scanning unit 1100.

The scanning unit 1100 may include an optical fiber 1103, a drivingrange adjustment means 1110, and a lens module 1200.

The optical fiber 1103 may be used as a light transfer path throughwhich the light transferred from the light-emitting unit 121 is emittedto the object.

Also, one end or the fixed end of the optical fiber 1103 may be coupledto the driving unit 1101.

Also, the other end of the optical fiber 1103 may be a free end vibratedby a force applied from the driving unit 1101.

In this case, the driving unit 1101 may apply a force to an actuatorposition P0 placed between the fixed end and the free end of the opticalfiber 1103. For example, the actuator position P0 may be a position onwhich a force generated when the piezoelectric material is deformed by adriving signal applied to the driving unit 1101 acts.

Accordingly, the free end of the optical fiber 1103 may perform ascanning operation according to a preset scanning pattern by a forceapplied from the driving unit 1101.

In an embodiment, the optical fiber 1103 may be a single optical fiberhaving a cylindrical shape and may be surrounded by the piezoelectricelement of the cylindrical structure.

In this case, the optical fiber may receive a first force from the firstactuating unit 1101 a and vibrate in the first direction and may receivea second force from the second actuating unit 1101 b and vibrate in thesecond direction.

Also, the free end of the optical fiber 1103 may receive the forcecaused by the deformation of the first actuating unit 1101 a and thesecond actuating unit 1101 b and then may vibrate and emit light along atrajectory of the optical fiber 1103. For example, the controller 130may apply the first driving signal and the second driving signal to thefirst actuating unit 1101 a and the second actuating unit 1101 b,respectively. The first actuating unit 1101 a and the second actuatingunit 1101 b may transfer a first force caused by applying the firstdriving signal and transfer a second force caused by applying the seconddriving signal to the optical fiber to drive the free end of the opticalfiber.

For example, the first driving signal is a first resonant frequency forresonantly driving the optical fiber in the first direction, and thesecond driving signal is a second resonant frequency for resonantlydriving the optical fiber in the second direction.

In general, when an object is driven using a resonant frequency, theobject tends to oscillate indefinitely, and thus it is possible toobtain a larger swing even if the same voltage is applied.

In an embodiment, when the free end of the optical fiber 1103 is set todraw a Lissajous pattern, the optical fiber 1103 may be designed to havedifferent resonant frequencies with respect to the first axis and thesecond axis. A method of setting the first resonant frequency and thesecond resonant frequency will be described in detail in the followingrelated sections.

Accordingly, when the driving unit 1101 is driven using the resonantfrequency of the optical fiber 1103, it is possible to implement largefields of view (FOVs) using even small voltages. Also, for example, thefirst resonant frequency and the second resonant frequency applied tothe driving unit 1101 may be determined depending on the length of theoptical fiber 1103, stiffnesses with respect to the first axis and thesecond axis of the optical fiber, etc.

Meanwhile, the driving unit 1101 and one end of the optical fiber 1103may be coupled to each other such that the optical fiber 1103 can beaccurately disposed at the center of the driving unit 1101.

For example, when the optical fiber is surrounded by the driving unit1101 having the cylindrical structure, at least a portion of the opticalfiber 1103 may be inserted into the driving unit 1101 and aligned withthe center of the driving unit 1101.

That is, by the optical fiber 1103 being aligned with the center of thepiezoelectric element of the cylindrical structure, the axis of a forceacting when the driving unit 1101 is moved by a driving signal appliedfrom the controller 130 may match the axis of a force acting when theoptical fiber 1103 is vibrated. A method of coupling the optical fiberand the driving unit will be described in detail in the followingrelevant sections.

The driving range adjustment means 1110 may be a structure for adjustinga scanning pattern that is drawn by the optical fiber 1103 so that theoptical fiber 1103 can be vibrated according to the preset scanningpattern.

As described above, in order for the optical fiber 1103 to draw aLissajous scanning pattern, the optical fiber 1103 may have differentdriving frequencies with respect to the first axis and the second axis.

This is because when the optical fiber 1103 is vibrated at the sameresonant frequency with respect to the first axis and the second axis,the optical fiber 1103 draws a circular scanning pattern.

In general, the resonant frequency fr of the optical fiber 1103 may bedetermined by Formula 1 below:

f _(r)=½√{square root over ((k/m))}  [Formula 1]

where k is the elastic modulus of a material, and m is the mass.

That is, referring to FIG. 1, the resonant frequency fr of the opticalfiber 1103 may vary depending on the elastic modulus k of the opticalfiber. The elastic modulus k of the optical fiber may be determineddepending on the stiffness of the optical fiber. When the single opticalfiber 1103 having a cylindrical shape is applied, the optical fiber 1103may have the same stiffness with respect to the first axis and thesecond axis, and thus the first resonant frequency with respect to thefirst axis of the optical fiber 1103 may be the same as the secondresonant frequency with respect to the second axis.

Accordingly, a structure having a predetermined elasticity may beattached to any one of the first axis and the second axis so that thestiffness of the optical fiber 1103 varies depending on the first axisand the second axis.

Also, for example, it may be necessary to design the structure so thatthe difference between the first resonant frequency and the secondresonant frequency of the optical fiber 1103 deviates from a presetrange. This is because when the difference between the first resonantfrequency and the second resonant frequency does not deviate from thepreset range, the Lissajous scanning pattern drawn by the optical fiber1103 may be distorted.

In an embodiment, the driving range adjustment means 1110 may beattached to the optical fiber 1103 in any one of a first axis directionand a second axis direction in which the optical fiber 1103 vibratessuch that the optical fiber 1103 has a structure asymmetrical withrespect to the first axis and the second axis.

In another embodiment, the driving range adjustment means 1110 may beattached to the optical fiber 1103 in both of the first axis directionand the second axis direction such that the optical fiber 1103 has astructure asymmetrical with respect to the first axis and the secondaxis.

Accordingly, the optical fiber 1103 may vibrate at different drivingfrequencies with respect to the first direction and the second directionand thus emit a Lissajous pattern that meets a predetermined criterion.

Also, for example, the driving range adjustment means 1110 may includeone or more of a mass, a deformable structure, and the like which areattached to any position on a z-axis or in the longitudinal direction ofthe optical fiber 1103.

In this case, the driving range in which the optical fiber 1103 vibratesmay be adjusted according to the length, size, shape, attachmentposition, attachment angle, and the like of the mass and the deformablestructure attached to the optical fiber 1103. A detailed structure ofthe driving range adjustment means 1110 will be described in detailthrough the following related embodiments.

1.4 Optical Module

A laser beam emitted from the optical module 120 through the opticalfiber 1103 may be directly emitted to an object through a distal end ofthe optical fiber 1103.

In this case, when light is radiated from the distal end of the opticalfiber 1103, it is difficult to generate an image of the object.

Optionally, a lens module 1200 for collecting light radiated from thedistal end of the optical fiber 1103 may be disposed at the distal endof the optical fiber 1103.

Alternatively, the distal end of the optical fiber 1103 may be processedsuch that light emitted through the optical fiber 1103 can be collected.For example, the distal end of the optical fiber 1103 may be processedinto a spherical shape. Accordingly, the laser beam collected at thedistal end of the optical fiber 1103 may be directly emitted to theobject.

Alternatively, by processing the distal end of the optical fiber 1103and further installing the lens module 1200 at the distal end of theoptical fiber 1103, it is possible to improve a numerical aperture (NA)at an output stage.

FIG. 8 is a diagram illustratively showing a beam that is output whenthe optical fiber 1103 is processed into a spherical shape according toanother embodiment of the present invention.

In general, resolution increases as an NA increases at an output stage,and also resolution increases and an FOA decreases as the magnificationof a lens decreases.

Accordingly, since the magnification of a lens is fixed, it may beadvantageous to use an optical fiber 1103 having a large NA.

In order to increase the NA of the optical fiber 1103, an end of theoptical fiber 1103 may be processed. For example, the end of the opticalfiber 1103 may be processed into a conical shape.

For example, the end of the optical fiber may be processed into thespherical shape by polishing a side surface of the optical fiber 1103 ina conical shape and polishing the end to be round.

In this case, NA1 of the optical fiber increases, and thus NA2 increasesat the output stage. Accordingly, an image with high resolution and noFOA loss may be obtained.

1.5 Lens Module

FIGS. 9 and 10 are diagrams for exemplarily describing a configurationof the lens module 1200 according to an embodiment of the presentinvention.

As described above, the scanning unit 1100 according to an embodiment ofthe present invention may further include the lens module 1200 forcollecting light radiated from the distal end of the optical fiber 1103.The lens module 1200 according to an embodiment of the present inventionmay be designed in consideration of processability of the lens moduleand distortion correction for high-resolution implementation.

Also, the lens module 1200 may be designed in an appropriate size inconsideration of the miniaturization of the scanning module 110.

Also, the lens module 1200 may include at least five lenses, and atleast one of the lenses may be formed as an aspherical lens.

For example, as shown in FIGS. 9 and 10, the lens module 1200 accordingto an embodiment of the present invention may include first lenses 1211and 1221, second lenses 1212 and 1222, third lenses 1213 and 1223,fourth lenses 1214 and 1224, fifth lenses 1215 and 1225, and sixthlenses 1216 and 1226.

Also, for example, the resolution and magnification may be optimizedaccording to a thickness and a ratio between a thickness and a diameterof each lens.

Also, for example, all of the first lenses 1211 and 1221, the secondlenses 1212 and 1222, the third lenses 1213 and 1223, the fourth lenses1214 and 1224, the fifth lenses 1215 and 1225, and the sixth lenses 1216and 1228 may be aspherical lenses.

The first lenses 1211 and 1221 are convergent lenses that collect lightentering the optical fiber 1103 and that make the light enter parallelto an optical axis thereof. The first lenses 1211 and 1221 can reduceperipheral optical efficiency losses by making the light enter parallelto the optical axis.

The second lenses 1212 and 1222 and the third lenses 1213 and 1223 arelenses for spherical aberration correction, and the fourth lenses 1214and 1224 and the fifth lenses 1215 and 1225 are lenses for sphericalaberration correction and chromatic aberration correction.

For example, the fourth lenses 1214 and 1224 and the fifth lenses 1215and 1225 may be coupled to each other in a symmetrical form in order toincrease the effect of the chromatic aberration correction.

Also, the sixth lenses 1216 and 1226 may be focusing lenses for finallyfocusing the light onto the object.

Also, a separate mounting device 5200 may be further provided to storethe scanning module 110 according to an embodiment of the presentinvention.

For example, the mounting device 5200 may have a space provided thereinto stably accommodate the scanning module 110.

Also, for example, the mounting device 5200 may further have a modulefor performing an initial calibration operation while the scanningmodule 110 is mounted. The calibration operation performed through themounting device 5200 will be described in detail in the followingrelevant sections.

2 Design Conditions of Scanning Unit

Design conditions of the scanning unit 1100 according to embodiments ofthe present invention will be described in detail below with referenceto FIGS. 11 to 29.

As described above, the scanning unit 1100 according to embodiments ofthe present invention may be designed to emit light according to aLissajous pattern.

For example, depending on preset conditions, an additional structuresuch as a mass and a deformable rod may be attached to the optical fiber1103 to perform a Lissajous pattern. The design of an additionalstructure for adjusting the driving range of the optical fiber 1103 sothat the optical fiber 1103 draws a Lissajous figure meeting a presetcondition will be described in detail below.

2.1 Mass

The overall rate and driving range of an optical fiber scanner may bedetermined by the length and weight of the optical fiber 1103.

Accordingly, upon designing the scanning unit 1100 according to anembodiment of the present invention, first, the length and weight of theoptical fiber 1103 may be determined to draw a scanning pattern meetinga preset condition.

Referring to FIG. 11, the scanning unit 1100 according to an embodimentof the present invention may have a mass M attached to a distal end ofthe optical fiber 1103.

For example, as shown in FIG. 11, in order to increase Q-factor of theoptical fiber 1103 and increase the driving range, a mass M having apreset weight may be attached to the distal end of the optical fiber1103.

In this case, the mass M may have a weight larger than the weight m ofthe optical fiber 1103. However, the following description will be basedon the length of the mass M because the mass M is a micrometer-scalemicrostructure and thus has a very small mass.

For example, when the mass M is attached to the distal end of theoptical fiber 1103 as shown in FIG. 11, the effective mass of theoptical fiber 1103 may be increased, and thus the driving rate of thescanning unit 1100 may be decreased. However, along with the increase inthe effective mass of the optical fiber 1103, the maximum amplitude atwhich the optical fiber 1103 vibrates may be increased.

Also, for example, the mass M may be a microstructure produced insilicon microprocessing and may have various shapes such as ahexahedron, a sphere, and other processable shapes.

In an embodiment, the length L of the optical fiber and the length ML ofthe mass may be determined according to a target frequency forimplementing a high scanning rate.

For example, both of the first resonant frequency of the first axisdirection and the second resonant frequency of the second axis directionmay be selected to be higher than or equal to 1 kHz.

In this case, the first axis and the second axis are different from eachother on an xyz-space. When the longitudinal direction of the opticalfiber 1103 indicates a z-axis, the first axis may be a y-axis, and thesecond axis may be an x-axis orthogonal to the first axis. Forconvenience of description, the first axis is the y-axis and the secondaxis is the x-axis as an example in the following description.

FIG. 12 is a graph for illustratively showing a change in resonantfrequency according to the length L of the optical fiber 1103 and thelength ML of the mass in the scanning unit 1100 according to anembodiment of the present invention.

For example, as shown in FIG. 12, it can be seen that the resonantfrequency increases as the length L of the optical fiber 1103 decreasesand that the resonant frequency decreases as the length ML of the massincreases.

Accordingly, the length L of the optical fiber 1103 and the length ML ofthe mass may be selected appropriately depending on the targetfrequency.

For example, referring to FIG. 12, when the target frequency is 1 kHz orhigher, one of a set of the length ML (=0.5 mm) of the mass M and thelength L (<=7 mm) of the optical fiber 1103 and a set of the length ML(=1 mm) of the mass M and the length L (<=6 mm) of the optical fiber1103 may be selected.

In this case, in order to appropriately select the length L of theoptical fiber 1103 and the length ML of the mass according to the targetfrequency, scanning amplitude may be further considered upon resonantdriving.

The design conditions of the scanning unit 1100 are exemplary, and thescanning unit 1100 may be designed in various ways in order to implementscanning patterns corresponding to other preset conditions.

2.2 Buffer Distance

The maximum amplitude at which the optical fiber 1103 is driven mayincrease as the mass M is attached closer to the free end of the opticalfiber 1103.

Accordingly, by further attaching the mass M to the distal end of theoptical fiber 1103, the FOV of an image obtained due to the vibration ofthe optical fiber 1103 may be expanded.

However, referring to FIG. 13, the mass M may be attached to the distalend of the optical fiber 1103. In this case, when the optical fiber 1103is vibrated by a force applied from the driving unit 1101, the mass Mattached to the distal end of the optical fiber 1103 may collide with aninner wall of the housing H. Also, in this case, the mass M is morelikely to be broken by frequent collisions with the inner wall of thehousing H, and thus the performance and durability of the scanningmodule 110 are degraded.

Furthermore, when the lens module 1200 is further installed as shown inFIG. 13, the mass M may collide with the lens module 1200, and the lensmodule 1200 may be damaged. When the lens module 1200 is damaged, thequality of the image reconstructed by the controller 130 may bedegraded.

Accordingly, it may be necessary to adjust the attachment position ofthe mass M so that the mass M does not directly collide with the lensmodule 1200 and/or the inner wall of the housing H.

FIG. 14 is a diagram for exemplarily describing the attachment positionof the mass M according to an embodiment of the present invention.

For convenience of description, an attachment distance for preventingthe mass M from being broken along with a collision with the inner wallof the housing H is defined as a buffer distance.

Relatively, the optical fiber 1103 may be resonantly driven by a forceapplied from the driving unit 1101. In this case, when an end of theoptical fiber 1103 having a smaller weight and a smaller area in contactwith the inner wall than the mass M is brought into contact with theinner wall of the housing H, the optical fiber 1103 may have a lowpossibility of being damaged by a collision with the inner wall of thehousing H.

Accordingly, in the case of the scanning unit 1100 according to anembodiment of the present invention, it is possible to prevent damagedue to a collision between the mass M and the inner wall of the housingH by attaching the mass M to the optical fiber 1103 while being spaced apredetermined distance from the distal end of the optical fiber 1103.

For example, the mass M may be attached between the fixed end and thefree end of the optical fiber 1103.

In this case, the attachment position of the mass M may be determined inconsideration of one or more factors for implementing a scanning patternaccording to a preset condition, for example, the resonant frequency,the scanning rate, the driving range adjustment for the optical fiber1103, and the like. For example, preferably, the mass M may be attachedadjacent to the free end of the optical fiber 1103 with respect to thehalf point of the total length L of the optical fiber in order toimprove the scanning rate and expand the FOV.

Also, for example, referring to FIG. 14, in order to improve thescanning rate, expand the FOV, and minimize breakage of the mass M dueto a collision with the inner wall of the housing H, the mass M may beattached between the half point of the total length L of the opticalfiber and the shortest end of the optical fiber.

That is, the buffer distance BD may be defined as Formula 2 below:

$\begin{matrix}{\frac{L}{2} < {BD} < {L.}} & \left\lbrack {{Formula}\mspace{14mu} 2} \right\rbrack\end{matrix}$

In this case, as shown in FIG. 14, it is possible to minimize acollision of the mass M with the inner wall of the housing H when theoptical fiber 1103 vibrates.

As an example, the buffer distance BD may be determined in furtherconsideration of the length ML of the mass M.

For example, when the buffer distance BD is at least greater than orequal to the length ML of the mass M, it is possible to prevent the massM from colliding with the inner surface of the housing H.

As another example, the buffer distance BD may be set on the basis ofthe inner diameter W of the housing H and the maximum driving ranges ofthe optical fiber 1103 and the mass M. This is to miniaturize thehousing H and to prevent damage to the optical fiber 1103 and the massM.

For example, referring to FIG. 14, it is assumed that when the opticalfiber 1103 vibrates within the housing H, the maximum driving range inwhich the optical fiber 1103 is vibrable is D1 from the center point ofthe inner diameter of the housing H, and the maximum driving range inwhich the mass M is vibrable is D2 from the center point of the innerdiameter of the housing H. Here, D1 and D2 may be defined as follows:

D1<½W, and

D2<½W.

In this case, D2 may indicate the highest point when the mass M moves tothe maximum driving range in which the optical fiber 1103 moves in thehousing H so that the mass M does not collide with the inner wall of thehousing H. Also, for example, the buffer distance BD may be determinedin consideration of all of the length ML of the mass, the maximumdriving ranges in which the optical fiber and the mass are vibrable inthe first axis, and the inner diameter of the housing H.

Accordingly, in the case of the scanning module 110 according to anembodiment of the present invention, it is possible to provide anoptical device with enhanced product performance and durability byminimizing breakage of elements packaged in the scanning module 110while miniaturizing the packaging of the scanning module 110.

2.3 Driving Range Adjustment Means

As described above, the driving range adjustment means 1110 may befurther attached to the optical fiber 1103 according to an embodiment ofthe present application to perform Lissajous scanning corresponding to apreset condition.

As described above, in order to implement a Lissajous pattern, theresonant frequency of the optical fiber 1103 may need to have differentvalues for the first axis and the second axis.

Also, as shown in the image (c) of FIG. 4, in order to implement theLissajous scanning corresponding to the preset condition, the differencebetween the resonant frequencies for the first axis and the second axismay need to deviate from the preset range. In this case, when thedifference between the resonant frequencies for the first axis and thesecond axis is not out of the preset range, the Lissajous patternemitted from the optical fiber 1103 may be distorted.

For example, the difference between the first resonant frequency fy forthe first axis of the optical fiber 1103 and the second resonantfrequency fx for the second axis of the optical fiber 1103 needs to beat least greater than or equal to the full-width half-maximum (FWHM) ofthe resonant frequency fr of the optical fiber 1103.

Alternatively, as shown in FIG. 15, the first resonant frequency fy andthe second resonant frequency fx of the optical fiber 1103 may beseparated by more than the full width (FW) of the resonant fr of theoptical fiber 1103.

Referring to FIG. 15, the difference between the first resonantfrequency fy and the second resonant frequency fx may be the FW of theresonant frequency fr, which is 200 Hz.

Accordingly, as described above, the optical fiber 1103 may be designedto have different stiffnesses k with respect to the first axis and thesecond axis by installing an elastic structure such that the opticalfiber 1103 has different resonant frequencies with respect to the firstaxis and the second axis.

In detail, the optical fiber 1103 may become an asymmetric structurewith respect to the first axis and the second axis by attaching adeformable rod to any one of the first axis and the second axis of theoptical fiber 1103. This is because the resonant frequencies of theoptical fiber 1103 in the first axis and the second axis may varydepending on the stiffnesses in the first axis and the second axis.

However, the ratio of the stiffness of the first axis to the stiffnessof the second axis of the optical fiber 1103 (k_(y)/kx) may be designednot to exceed one. Since the driving range (displacement) of the scannervaries depending on the stiffness of each axis, the FOV of the imagereconstructed by the controller 130 may not be properly secured when thestiffness ratio of each axis is increased.

FIG. 16 is a diagram for exemplarily describing a structure of thedriving range adjustment means 1110 according to an embodiment of thepresent invention. Referring to FIG. 16, the driving range adjustmentmeans 1110 may include a first connector 1111, a deformable rod 1112,and a second connector 1113.

As described above, the driving range adjustment means 1110 may bedesigned such that the optical fiber 1103 has an asymmetric structurewith respect to the first axis and the second axis. In the asymmetricstructure, the difference in resonant frequency between the first axisand the second axis of the optical fiber 1103 is out of a preset range.Accordingly, the optical fiber 1103 may emit a Lissajous pattern with nocoupling. The coupling of the Lissajous pattern emitted by the opticalfiber 1103 will be described in detail in the following relatedsections.

For convenience of description, the following description assumes thatthe controller 130 applies a first driving frequency to a firstactuating unit 1101 a and applies a second driving frequency to a secondactuating unit 1101 b.

Also, the first actuating unit 1101 a and the second actuating unit 1101b are PZT material-based piezoelectric elements as an example in thefollowing description. For example, the controller 130 may apply thefirst driving frequency and the second driving frequency to the firstactuating unit 1101 a and the second actuating unit 1101 b, and thefirst actuating unit 1101 a and the second actuating unit 1101 b may bemechanically deformed.

In this case, a force generated due to the mechanical deformation of thefirst actuating unit 1101 a and the second actuating unit 1101 b may betransferred to the first axis and the second axis of the optical fiber1103, and the optical fiber 1103 may be vibrated in the first axis andthe second axis by the force transferred from the first actuating unit1101 a and the second actuating unit 1101 b.

Also, the first driving frequency applied to the first actuating unit1101 a may cause the optical fiber 1103 to vibrate along the first axis,and the second driving frequency applied to the second actuating unit1101 b may cause the optical fiber 1103 to vibrate along the secondaxis. The deformable rod 1112 may be an elastic structure to be attachedto at least one of the first axis and the second axis of the opticalfiber 1103 in order to change the stiffness of the optical fiber 1103with respect to at least one of the first axis and the second axis.

For example, the optical fiber 1103 may be resonantly driven due to afirst force applied from the first actuating unit 1101 a and a secondforce applied from the second actuating unit 1101 b, and the deformablerod 1112 may change the stiffness of at least one of the first axis andthe second axis of the optical fiber 1103 when the optical fiber 1103 isresonantly driven.

In this case, the optical fiber 1103 may have a first stiffness, and thedeformable rod 1112 may have a second stiffness. In this case, thesecond stiffness may be greater than or equal to the first stiffness.

In an embodiment, the deformable rod 1112 may be attached onto the firstaxis of the optical fiber 1103 in order to amplify the vibration of theoptical fiber 1103 in the first axis direction.

In this case, since the stiffness of at least one of the first axis andthe second axis of the optical fiber 1103 changes, the optical fiber1103 may be an asymmetric structure with respect to the first axis andthe second axis. Accordingly, a difference in resonant frequency withrespect to the first axis and the second axis of the optical fiber 1103occurs.

In this case, the deformable rod 1112 may be formed of a material with apredetermined elastic force in order to amplify the vibration along thefirst axis or the second axis of the optical fiber 1103.

Also, the deformable rod 1112 may have various shapes.

For example, as shown in FIG. 16, the deformable rod 1112 may have theshape of a rectangular bar or wire.

Also, the deformable rod 1112 may be disposed adjacent to the opticalfiber 1103 in the longitudinal length of the optical fiber 1103, i.e.,in the z-axis direction and may be spaced a predetermined distance fromthe optical fiber 1103.

Also, the deformable rod 1112 may have a first end and a second end.

For example, referring to FIG. 16, the first end of the deformable rod1112 may be fixed at a first rod position P1 on the optical fiber 1103,and the second end may be fixed at a second rod position P2 on theoptical fiber 1103.

In this case, the first rod position P1 and the second rod position P2may be between the actuator position P0 and the free end of the opticalfiber 1103.

Here, the actuator position P0 may be a position to which a force forvibrating the optical fiber is transferred according to the drivingsignals applied to the first actuating unit 1101 a and the secondactuating unit 1101 b.

For example, the actuator position P0 may be between the fixed end andthe free end of the optical fiber 1103.

In this case, the first actuating unit 1101 a may be configured to applya first force to the actuator position P0 and may induce the free end ofthe optical fiber 1103 to be resonantly driven in a first direction.

Also, the second actuating unit 1101 b may be configured to apply asecond force to the actuator position P0 and may induce the free end ofthe optical fiber 1103 to be resonantly driven in the first direction.

Meanwhile, one or more deformable rods 1112 may be installed such thatthe resonant frequencies for the first axis and the second axis areseparated beyond a predetermined range to emit a Lissajous patterncorresponding to a preset condition while having different resonantfrequencies with respect to the first axis and the second axis.

Also, referring to FIG. 16, the first connector 1111 and the secondconnector 1113 may be fixers or microstructures for supporting thedeformable rod 1112.

For example, the first connector 1111 and the second connector 1113 maybe silicon microstructures and may be produced by silicon wafermicroprocessing.

Alternatively, for example, the first connector 1111 and the secondconnector 1113 may be adhesive agents which fix the deformable rod 1112on the optical fiber 1103 while being spaced a predetermined distancefrom the optical fiber 1103.

Also, for example, the first connector 1111 and the second connector1113 may be attached to the z-axis of the optical fiber 1103.

In this case, the deformable rod 1112 may be positioned between thefirst connector 1111 and the second connector 1113, and the first endand the second end of the deformable rod 1112 may be connected to eachother by the first connector 1111 and the second connector 1113.

Also, for example, the first connector 1111 and the second connector1113 may be fixers that are fixed at the optical fiber 1103. In thiscase, a predetermined groove may be formed in the first connector 1111and the second connector 1113 such that the first connector 1111 and thesecond connector 1113 are stably fixed on the optical fiber 1103.

Also, the first connector 1111 and the second connector 1113 may bedesigned in various shapes as long as the first connector 1111 and thesecond connector 1113 are fixed on the optical fiber 1103 to support thedeformable rod 1112.

In an embodiment, the first connector 1111 and the second connector 1113that support the deformable rod 1112 and the first end and the secondend of the deformable rod 1112 may move along with the vibration of theoptical fiber 1103.

In this case, the deformable rod 1112 may amplify the vibration of theoptical fiber 1103 in the first axis direction when the optical fiber1103 vibrates in the first axis direction according to the first forceapplied from the first actuating unit 1101 a to the actuator positionP0.

Alternatively, the deformable rod 1112 may amplify the vibration of theoptical fiber 1103 in the second axis direction when the optical fiber1103 vibrates in the second axis direction according to the second forceapplied from the second actuating unit 1101 b to the actuator positionP0.

Accordingly, the optical fiber 1103 may have different resonantfrequencies for the first axis and the second axis.

However, the vibration in the second axis direction may be amplified bya portion of the force applied in the first axis direction beingtransferred to the second axis direction of the optical fiber 1103.Also, the vibration in the first axis direction may be amplified by aportion of the force applied in the second axis direction beingtransferred to the first axis direction of the optical fiber 1103.

In this case, when the attachment position and direction of thedeformable rod 1112 are appropriately designed, a portion of a forceapplied to any one axis may affect the other axis, and thus it ispossible to decrease amplification of the vibration in the other axis.This will be described in detail in the following related sections.

2.4 Deformable Rod Attachment Position

As described above, by attaching the deformable rod 1112 to any one ofthe first axis and the second axis along which the optical fiber 1103 isdriven when the scanning unit 1100 according to an embodiment of thepresent invention is designed, the optical fiber 1103 may have differentresonant frequencies with respect to the first axis and the second axis.

A method of determining the attachment position of the deformable rod1112 such that the difference between the resonance frequencies of thefirst axis and the second axis of the optical fiber 1103 is out of apreset range will be described in detail below.

FIG. 17 is a diagram for describing the attachment position of thedeformable rod for designing the difference between the resonantfrequencies of the first axis and the second axis of the optical fiber1103 as deviating from a preset range in an embodiment of the presentinvention.

That is, since the difference in resonant frequency between the firstaxis and the second axis of the optical fiber 1103 may vary depending onthe attachment position of the deformable rod 1112, it may be necessaryto adjust the installation position L1 and length L2 of the deformablerod 1112.

For example, the installation position L1 of the deformable rod 1112 maybe determined based on the distance from the fixed end of the opticalfiber 1103 to the half point of the total length L2 of the deformablerod 1112.

For example, as shown in FIG. 17, the deformable rod 1112 may bedisposed alongside and spaced a predetermined distance from the opticalfiber 1103 and may be installed at a position spaced L1 apart from oneend of the optical fiber 1103.

Also, for example, the deformable rod 1112 may be installed and spaced apredetermined distance L3 apart from the mass M installed at a distalend of the optical fiber 1103.

In this case, the first connector 1111 and the second connector 1113 maybe designed to have a much smaller mass than the mass M. Alternatively,the first connector 1111 and the second connector 1113 may be designedto have a mass greater than or equal to that of the mass M.

FIG. 18 is a diagram for exemplarily describing the structure of adriving range adjustment means 1110 according to another embodiment ofthe present invention.

Referring to FIG. 18, the driving range adjustment means 1110 accordingto another embodiment of the present invention may include a firstconnector 1111, a deformable rod 1112, and a second connector 1113, andthe mass M described with reference to FIG. 17 may also function as thesecond connector 1113.

In other words, for a scanning unit 1100 according to another embodimentof the present invention, the deformable rod 1112 may be supported bythe first connector 1111 and the mass M.

Accordingly, the installation position L1 and the length L2 of thedeformable rod 1112 according to another embodiment of the presentinvention may differ from those when a separate mass M is installed.

This is because the mass M needs to be installed at an appropriateposition to perform a function for adjusting the driving speed of thescanning unit 1100 and also to function as an auxiliary member forsupporting the deformable rod 1112.

For example, referring to FIG. 18, the deformable rod 1112 according toanother embodiment of the present invention may be installed at locationL11 spaced a predetermined distance from one end of the optical fiber1103. As described above with reference to FIG. 14, the buffer distancefrom the inner wall of the housing may be additionally considered.

Also, by attaching an additional structure to the optical fiber 1103 asdescribed above, distortion may still occur in a scanning patternemitted by the optical fiber 1103 depending on the attachment directionof the deformable rod 1112 even when the optical fiber 1103 is designedto have different resonant frequencies with respect to the first axisand the second axis.

This is because when the optical fiber 1103 vibrates in the firstdirection due to the first force applied from the first actuating unit1101 a, the vibration is amplified not only in the first direction butalso in the second direction.

Alternatively, this is because when the optical fiber 1103 vibrates inthe second direction due to the second force applied from the secondactuating unit 1101 b, the vibration is amplified not only in the seconddirection but also in the first direction.

A phenomenon in which a force transferred in one axial direction affectsthe other axial direction and amplifies the vibration in the other axialdirection is defined below as cross-coupling.

2.5 Cross-Coupling

The cross-coupling and the attachment direction of the deformable rodfor removing the cross-coupling will be described in detail below.

FIG. 19 is a diagram for exemplarily describing illustratingcross-coupling according to an embodiment of the present invention.

For example, when the controller 130 applies a first driving signal tothe first actuating unit 1101 a, a portion of a force that should havebeen transferred to only the first axis of the optical fiber 1103 may betransferred to the second axis, and cross-coupling corresponding to thetransferred force may occur along the second axis.

In this case, as shown in the image (b) of FIG. 19, mechanical couplingor a coupled Lissajous pattern may be generated in the second axisdirection.

Alternatively, for example, when the controller 130 applies a seconddriving signal to the second actuating unit 1101 b, a portion of a forcethat should have been transferred to only the second axis of the opticalfiber 1103 may be transferred to the first axis, and cross-couplingcorresponding to the transferred force may occur along the first axis.

In this case, as shown in the image (a) of FIG. 19, mechanical couplingor a coupled Lissajous pattern may be generated in the first direction.

For convenience of description, the mechanical coupling or the coupledLissajous pattern is defined as a coupling error.

Here, the coupling error may be generated by various causes.

For example, when the optical fiber 1103 is vibrated by a forcetransferred from the PZT-device-based driving unit 1101 to the actuatorposition P0 on the optical fiber 1103, the vibration may occur when theforce axes (x-axis and y-axis) of the optical fiber 1103 do not matchthe resonant driving axes (x′-axis and y′-axis) in which the opticalfiber 1103 is actually driven.

Alternatively, for example, since the driving unit 1101 is not perfectlycircular, the center of the inner diameter does not match the center ofthe outer diameter. Thus, it may not be possible to drive the drivingunit 1101 such that the force axes (x-axis and y-axis) of the opticalfiber 1103 match the resonant driving axes (x′-axis and y′-axis) inwhich the optical fiber 1103 actually vibrates.

In this case, by adjusting the attachment position and/or direction ofthe deformable rod 1112 installed at the optical fiber 1103, the forceaxes (x-axis and y-axis) transferred to the optical fiber 1103 may beadjusted to match the resonant driving axes (x′-axis and y′-axis) of theoptical fiber 1103. This is because the resonant driving axis of theoptical fiber 1103 may vary depending on the attachment position and/ordirection of the deformable rod 1112.

However, even if the force axes of the optical fiber 1103 and theresonant driving axes do not match perfectly, a predetermined error maybe allowed when an image reconstructed on the basis of the scanningpattern emitted from the optical fiber 1103 has a quality more than orequal to a preset level.

2.6 Attachment Range of Deformable Rod

An attachment range determination method for the deformable rod 1112 tominimize the coupling error will be described in detail below.

As described above, while being supported by the first connector 1111and the second connector 1113, the deformable rod 1112 may change thestiffness of at least one of the first axis and the second axis of theoptical fiber 1103 such that the optical fiber 1103 has differentresonant frequencies with respect to the first axis and the second axis.

As described above, the deformable rod 1112 may have a first end fixedat the first rod position on the optical fiber 1103 and a second endfixed at the second rod position on the optical fiber 1103.

Thus, the deformable rod 1112 may function to amplify the vibration inthe first axis or in the second axis while being supported by the firstconnector 1111 and the second connector 1113.

That is, referring to FIG. 20, when the deformable rod 1112 vibratesaccording to a force applied to the optical fiber 1103, compression Cand expansion E may amplify the vibration of the optical fiber 1103.

The compression C and expansion E of the deformable rod 1112 may occurboth in the first axis direction and in the second axis directiondepending on the attachment direction of the deformable rod 1112.

For example, when the deformable rod 1112 is disposed parallel to theoptical fiber 1103, the compression C and expansion E of the deformablerod 1112 may occur only in the first axis direction.

FIGS. 21 and 22 are sectional views for describing an attachmentposition of a deformable rod according to embodiments of the presentinvention.

For example, on a cross-sectional surface perpendicular to the z-axisdirection or the longitudinal direction of the optical fiber 1103, theattachment position of the deformable rod may be determined such that avirtual line A2 connected from the second end of the deformable rod 1112to the second rod position on the second optical fiber matches a firstaxis A1. This is because a resonant driving axis along which the opticalfiber 1103 is actually driven is determined by a virtual line A2connected from the second end of the deformable rod 1112 to the secondrod position on the second optical fiber.

For convenience of description, the deformable rod 1112 is positioned inthe first axis direction of the optical fiber 1103 as an example in thefollowing description.

For example, when the attachment position of the deformable rod 1112 isdetermined such that the force axis (the first axis) of the opticalfiber 1103 matches the resonant driving axis along which the opticalfiber 1103 is actually driven, the resonant frequencies with respect tothe first axis and the second axis of the optical fiber 1103 may beseparated beyond a preset range as shown in the FIG. 23.

Referring to FIG. 21, it can be seen that the force axis A1 of theoptical fiber 1103 does not match the resonant driving axis A2 in whichthe optical fiber 1103 is actually driven.

In this case, when the controller 130 applies a first driving signal tothe first actuating unit 1101 a, the vibration of the optical fiber 1103induced by the first force applied from the first actuating unit 1101 ato the actuator position on the optical fiber 1103 may be amplified notonly in the first axis direction but also in the second axis, and thus apredetermined coupling error r may occur as shown in the image (b) ofFIG. 19.

Alternatively, when the controller 130 applies a second driving signalto the second actuating unit 1101 b, the vibration of the optical fiber1103 induced by the second force applied from the second actuating unit1101 b to the actuator position on the optical fiber 1103 may beamplified not only in the second axis direction but also in the firstaxis direction, and thus a predetermined coupling error r may occur asshown in the image (a) of FIG. 19.

On the contrary, referring to FIG. 22, it can be seen that the forceaxis A1 of the optical fiber 1103 matches the resonant driving axis A2.

In this case, as shown in FIG. 24, a Lissajous pattern with no couplingmay be generated.

The attachment position of the deformable rod 1112 for allowing apredetermined coupling error will be described below with reference toFIGS. 24 to 27.

As described above, on the cross-sectional surface perpendicular to thez-axis direction or the longitudinal direction of the optical fiber1103, the attachment position of the deformable rod may be determined onthe basis of an angle θ between the first direction A1 and the virtualline A2 connected from the second end of the deformable rod 1112 to thesecond rod position on the second optical fiber.

In an embodiment, the attachment position P1 of the deformable rod 1112may be determined to be away from the optical fiber 1103 on the virtualline A2.

For example, the deformable rod 1112 may be spaced a predetermineddistance from the optical fiber 1103.

Alternatively, for example, the deformable rod 1112 may be installedsubstantially parallel to the optical fiber 1103.

Alternatively, the deformable rod 1112 may be disposed alongside theoptical fiber 1103.

Alternatively, the deformable rod 1112 may be disposed to at leastpartially overlap the optical fiber 1103.

For convenience of description, the following description assumes that apredetermined coupling error r occurs in the second direction of theoptical fiber 1103 when the first actuating unit 1101 a is resonantlydriven. Under the assumption, an attachment angle range of thedeformable rod 1112 to minimize the coupling error will be described.

For example, as shown in FIG. 25, the angle θ between the first axisdirection A1 and the virtual line A2 connected from the attachmentposition P1 of the deformable rod 1112 to the second rod position on theoptical fiber may range from −b to +a with respect to the first axisdirection A1, that is, may range within a total of 10 degrees. In thiscase, a and b may have different values.

Alternatively, for example, the angle θ between the first axis directionA1 and the virtual line A2 connected from the attachment position P1 ofthe deformable rod 1112 to the second rod position on the optical fibermay range from −b to +a with respect to the first axis direction A1,that is, may range within a total of 5 degrees. In this case, a and bmay have different values.

In this case, the attachment angle range θ may be a value calculatedaccording to a preset criterion.

The preset criterion may have an allowable coupling error r that isreflected to maintain, at a certain level or more, the resolution of animage reconstructed on the basis of the scanning pattern emitted by theoptical fiber 1103.

As an example, when a first driving signal is applied to the firstactuating unit 1101 a, the attachment angle range θ may be calculated inconsideration of efficiency a of a force generated in the second axisdirection of the optical fiber 1103 due to the first force applied fromthe first actuating unit 1101 a to the actuator position of the opticalfiber 1103 and also efficiency b of a driving range in the second axisdirection of the optical fiber 1103.

For example, when a force equal to Fy is applied from the firstactuating unit 1101 a to the actuator position of the optical fiber 1103in the first axis direction (the y-axis), a predetermined force may betransferred to the second axis (the x-axis), and thus the vibration maybe amplified in the second axis direction.

Y=F _(y) cos θ.  [Formula 3]

X′=F _(y) sin θ.  [Formula 4]

Here, Formula 3 indicates a force Y transferred to the y-axis, andFormula 4 indicates a force X′ transferred to the x-axis.

In this case, the efficiency a of the force generated in the x-axisdirection in order to form a driving range equal to FOVx may be definedas follows:

$\begin{matrix}{a = {\frac{F_{y}\sin \theta}{F_{x}\cos \theta}.}} & \;\end{matrix}$

In this case, the driving range r in the x-axis direction may be definedas follows:

$r = {\frac{F_{y}\sin \theta}{F_{x}\cos \theta}*{FOV}_{x}*{b.}}$

FIG. 25 is a graph for illustratively showing an x-axis directiondriving range that is induced by a force transferred from the firstactuating unit 1101 a while in the scanning module 110 according to anembodiment of the present invention, and the deformable rod 1112 isinstalled alongside and on the optical fiber 1103 and the resonantfrequencies of the x-axis and the y-axis are separated by A.

FOV_(x)=pixels*resolution.

Here, when the number of pixels is 256 and the resolution is 1 um, thex-axis direction driving range r may be defined as follows:

$r = {\frac{F_{y}}{F_{x}}\tan \; \theta*256*{b.}}$

In an embodiment, the second-axis (x-axis) direction driving range r maybe allowed within at least ½ of a preset system resolution.

For example, when the second-axis (x-axis) direction driving range r isdetermined within ½ of one pixel, pixels can be distinguished from eachother, and thus it is possible to maintain the resolution of thereconstructed image at a preset level.

In this case, when the second-axis (x-axis) direction driving range r iswithin ½ of the preset system resolution, the attachment angle range θof the deformable rod 1112 is as follows:

$\therefore{\theta \leq {{\tan^{- 1}\left( {\frac{0.5}{256 \cdot b}\frac{F_{x}}{F_{y}}} \right)}.}}$

Here, θ may be defined as the attachment angle range of the deformablerod 1112 that allows a predetermined driving range r or coupling error rin the x-axis direction upon resonant driving in the y-axis direction.

That is, the attachment angle range of the deformable rod 1112 may becalculated in consideration of at least one of a system resolution, thetotal number of pixels, the maximum driving range of the first axis orthe second axis, and the efficiency of a force transferred in the firstaxis or the second axis.

Also, FIG. 26 is a graph for exemplarily describing an attachment angleof the deformable rod 1112 according to the driving range efficiency bin the second axis (x-axis direction) when Fx is equal to Fy.

Referring to FIG. 26, when it is assumed that the efficiency b of thesecond-axis (x-axis) direction driving range is between 1% and 20%, anattachment angle to allow a predetermined coupling error may range up to10 degrees.

In an embodiment, when a first-axis direction driving signal is appliedto the first actuating unit 1101 a, the attachment position or theattachment angle of the deformable rod 1112 may be determined such thatthe driving range of the optical fiber 1103 induced in the second axisdirection is less than 10% of the maximum driving range induced in thefirst axis direction.

In an embodiment, when the efficiency of the driving range in the secondaxis direction is less than 3%, the attachment angle range of thedeformable rod 1112 may be less than 4 degrees (θ≤4).

In conclusion, in embodiments of the present invention, it is possibleto allow the coupling error r within a range in which the quality of thereconstructed image may be maintained at a certain level or more.

Accordingly, by appropriately attaching the deformable rod 1112according to an embodiment of the present invention onto the opticalfiber 1103 in the allowable coupling error r, when the optical fiber1103 vibrates in one axis direction by a force applied from the firstactuating unit 1101 a or the second actuating unit 1101 b, vibration inanother axis direction may be prevented.

2.7 Frequency Characteristics

FIGS. 27 to 30 are diagrams showing frequency characteristics accordingto an attachment direction of the deformable rod 1112.

For convenience of description, the following description assumes thatat least one deformable rod 1112 is installed a predetermined distanceapart from the optical fiber 1103 and is attached within the attachmentangle range so that the resonant frequencies for the first axis and thesecond axis of the optical fiber are sufficiently separated.

As described above, when the deformable rod 1112 is attached to any oneof the first axis and the second axis of the optical fiber 1103, theelastic modulus k of the axis to which the deformable rod 1112 isattached may increase. This is because it is assumed that the stiffnessof the optical fiber 1103 of the axis to which the deformable rod 1112is attached increases when the k-value influence of the deformable rod1112 is greater than that of the mass M.

Accordingly, as the stiffness of the axis to which the deformable rod1112 is attached increases, the value of the driving frequency of theaxis to which the deformable rod 1112 is attached may increase.

For example, referring to FIG. 27, when the deformable rod 1112 isattached to the side fy, the graph may show fx<fr<fy.

On the other hand, referring to FIG. 28, when the deformable rod 1112 isattached to the side fx, the graph may show fy<fr<fx.

In this case, the maximum driving ranges in which the optical fiber 1103vibrates in the x-axis and the y-axis may vary depending on thedifference in driving frequency between the x-axis and the y-axis. Thatis, the vibration amplitude of the optical fiber 1103 varies.

Accordingly, the aspect ratio of the x-axis to the y-axis of thescanning pattern emitted by the optical fiber 1103 may vary.

In this case, in the image generating device 1 according to anembodiment of the present invention, the image aspect ratio of thex-axis to the y-axis, which is output from the image generating device1, may not be 1:1.

As an example, an aspect ratio that is output when the deformable rod1112 is attached to the y-axis direction, when the resonant frequency ofthe x-axis is 1100 Hz, and when the resonant frequency of the y-axis is1300 Hz may be calculated as follows:

F=kx.

First, it can be seen that when the same force F is given in the aboveformula, the spring constant K is inversely proportional to theamplitude x of the optical fiber 1103. Accordingly, the reciprocalk_(y)/k_(x) of the proportion of the value k for each axis may beassumed as an aspect ratio A.

This is expressed using the following formula:

$f_{x} = {\frac{1}{2\pi}\sqrt{\frac{k_{x}}{m}}}$$f_{y} = {\frac{1}{2\pi}\sqrt{\frac{k_{y}}{m}}}$

where k_(x) is a spring constant for the x-axis, k_(y) is a springconstant for the y-axis, and m is a mass.

$\sqrt{\frac{k_{x}}{k_{y}}} = {{\frac{f_{x}}{f_{y}}r\frac{k_{x}}{k_{y}}} = \frac{f_{x}^{2}}{f_{y}^{2}}}$${\Delta \; f} = {{f_{y} - {f_{x}\left( {{{if}\mspace{14mu} f_{y}} > f_{x}} \right)}} \geq \frac{FW}{2} \approx {200\; ({hz})}}$f_(x)² = Af_(y)²

Here, since Fx=1100,

$\frac{1}{A} = {\frac{k_{y}}{k_{x}} \approx {1.4.}}$

Accordingly, referring to the graph shown in FIG. 28, when thedeformable rod 1112 is attached to the y-axis direction, when theresonant frequency of the x-axis is 1100 Hz, and when the resonantfrequency of the y-axis is 1300 Hz, the aspect ratio of the scanningpattern emitted by the optical fiber 1103 (FOVy:FOVx) is approximately1:1.4.

In an embodiment, the attachment direction of the deformable rod 1112may be determined in consideration of a preset aspect ratio.

In another embodiment, the controller 130 may adjust the aspect ratio ofan image output through a display device by means of voltage control.

Alternatively, the controller 130 may adjust the aspect ratio of thescanning pattern emitted by the optical fiber 1103 by adjusting avoltage applied to the first actuating unit 1101 a and the secondactuating unit 1101 b.

For example, when the deformable rod 1112 is attached to the y-axisdirection, when the resonant frequency of the x-axis is 1100 Hz, andwhen the resonant frequency of the y-axis is 1300 Hz, the controller 130may adjust the image aspect ratio to be 1:1 by applying a higher voltageto the y-axis than to the x-axis. Alternatively, for example, thecontroller 130 may apply the same voltage to the first actuating unit1101 a and the second actuating unit 1101 b such that the output imagehas different aspect ratios with respect to the x-axis and the y-axis.

Alternatively, for example, the controller 130 may correct the aspectratio of an output image by applying a first voltage to the firstactuating unit 1101 a and applying a second voltage to the secondactuating unit 1101 b.

Alternatively, for example, the controller 130 may correct an image onthe basis of aspect ratio information entered by a user.

FIG. 31 is a flowchart for exemplarily describing an aspect ratiocorrection method according to an embodiment of the present invention.

Referring to FIG. 31, the aspect ratio correction method according to anembodiment of the present invention may include receiving aspect ratioinformation from a user (S11), determining voltages to be applied to afirst axis and a second axis on the basis of the aspect ratioinformation received from the user (S12), generating an imagecorresponding to an aspect ratio (S13), and the like.

As an example, the following description assumes that in the case of thescanning unit 1100 according to an embodiment of the present invention,the deformable rod 1112 is attached in the y-axis direction of theoptical fiber 1103, the resonant frequency of the x-axis is set to 1100Hz, and the resonant frequency of the y-axis is set to 1300 Hz so that aforce transferred to any one axis of the optical fiber 1103 does notmaximize the vibration in another axis.

In this case, as calculated through the above formula, the system aspectratio may be set such that FOVy:FOVx=1:1.4.

First, the controller 130 may receive aspect ratio information from auser (S11).

For example, the user may enter a request corresponding to a change inaspect ratio through the input unit in order to observe an imagecorresponding to a desired aspect ratio. For example, a plurality ofmodes may be preset for the image generating device 1 according to anembodiment of the present invention in order to convert a generatedimage into an image corresponding to a predetermined ratio.

In this case, the controller 130 may acquire the aspect ratioinformation received through the input unit and additionally checkpreset system resolution information.

Also, the controller 130 may determine voltages to be applied to thefirst axis and the second axis on the basis of the aspect ratioinformation received from the user.

For example, when the aspect ratio information received from the user inoperation S11 is a:b, the controller 130 may generate an imagecorresponding to the aspect ratio information by applying a firstvoltage to the x-axis and applying a second voltage to the y-axis.

Alternatively, for example, when the aspect ratio information receivedfrom the user in operation S11 is 1:1, the controller 130 may performcontrol such that a higher voltage is applied to the y-axis than to thex-axis.

Also, the controller 130 may generate an image corresponding to theaspect ratio (S13).

For example, the controller 130 may convert an image into an imagecorresponding to an aspect ratio desired by a user on the basis of theaspect ratio information received in operation S 11 and voltageinformation determined in operation S12 and may provide the imagecorresponding to the desired aspect ratio.

Accordingly, according to a Lissajous scanning scheme according to anembodiment of the present invention, an attachment position of adeformable rod 1112 that is additionally attached to the optical fiber1103 may be determined according to a preset image aspect ratio.

In other words, the controller 130 may correct an image to an imagehaving a ratio desired by a user and provide the image having thedesired ratio by adjusting the first driving signal for the first axisand the second driving signal for the second axis which are to beapplied to the driving unit 1101.

3 Packaging

FIGS. 32 to 34 are diagrams for exemplarily describing a couplingstructure for accommodating elements inside a housing of the scanningmodule 110 according to embodiments of the present invention.

As described above, the scanning module 110 according to embodiments ofthe present invention may be provided in the form of a handheld opticalfiber probe. In this case, various types of fixing elements may beprovided for compactly and firmly packaging elements in the probe.

The structure and the coupling method of a fixing element for packagingthe driving unit 1101 and the optical fiber 1103 in the housing H willbe described in detail below.

Also, for example, the following description assumes that the drivingunit 1101 is a PZT material-based piezoelectric element and that apiezoelectric element having a cylindrical structure is applied.

First, referring to FIG. 32, a first fixing element 1104 for matchingthe center of the driving unit 1101 to the center of the optical fiber1103 may be provided for the optical fiber probe according toembodiments of the present invention.

For example, as shown in FIG. 32, the first fixing element 1104 may havethe shape of a cylindrical ring.

Also, for example, the first fixing element 1104 may be formed of anon-conductive material because four electrodes of the driving unit mayneed to be insulated from each other.

Also, for example, the outer diameter OD1 of the first fixing element1104 may be designed to be a predetermined size larger or smaller thanthe inner diameter ID1 of the driving unit 1101. As an example, theinner diameter ID1 of the driving unit 1101 is about 0.9 mm, and theouter diameter OD1 of the first fixing element 1104 may be about 0.904mm.

Also, for example, the inner diameter ID of the first fixing element1104 is designed to be a predetermined size larger than the outerdiameter OD1 of the optical fiber 1103, and thus it is possible tofacilitate the assembly of the optical fiber 1103 and the driving unit1101.

For example, the optical fiber 1103 may pass through the first fixingelement 1104 and then be aligned such that the center of the opticalfiber 1103 is positioned at the center of the driving unit 1101.

Also, referring to FIG. 33, a second fixing element 1107 for supportingone end of the housing H may be further provided for the optical fiberprobe according to embodiments of the present invention.

For example, the outer diameter OD2 of the second fixing element 1107may be designed in consideration of the inner diameter of the tube ofthe housing H, and the inner diameter ID2 of the second fixing element1107 may be considered in consideration of the outer diameter of thedriving unit 1101.

Referring to FIG. 34, a third fixing element 1105 for fixing one end ofthe optical fiber 1103 to the PZT element may be provided for theoptical fiber probe according to embodiments of the present invention.

For example, in the case of the optical fiber probe, the PZT element maybe aligned with the center of the optical fiber 1103 by the third fixingelement 1105.

For example, the inner diameter ID3 of the third fixing element 1105 maybe designed in consideration of the outer diameter OD3 of the opticalfiber 1103. Also, for example, the outer diameter OD3 of the thirdfixing element 1105 may be determined in consideration of the innerdiameter D3 of the driving unit 1101.

In this case, the third fixing element 1105 may be inserted from thefront end of the optical fiber, which has passed through the firstfixing element 1104 and the driving unit 1101, up to the inside of thedriving unit 1101.

Accordingly, the optical fiber 1103 and the driving unit 1101 of theoptical fiber probe according to an embodiment of the present inventionmay remain aligned and coupled to each other by the third fixing element1105.

In this case, an adhesive may be used for the optical fiber 1103 tomaintain the coupling force with the driving unit 1101. For example,ultraviolet (UV)-curable or heat-curable epoxy may be used as theadhesive.

In this case, it may be preferable to symmetrically use a minimal amountof adhesive because an error may occur in the length of the opticalfiber 1103 depending on the amount of adhesive.

Also, according to still another embodiment of the present invention,one or more modules for maintaining the internal temperature of theprobe at a constant level may be disposed inside the housing of theoptical fiber probe.

That is, at least one temperature sensor or temperature adjustment meansmay be disposed inside the scanning module 110 according to stillanother embodiment of the present invention.

For example, in the case of an optical fiber probe used in hospitals inorder to diagnose diseases, an actual operational difference may occurdepending on the usage environment such as operating room temperatureand/or living body temperature.

As an example, the resonant frequency of the optical fiber may changewhen the internal temperature of the housing of the optical fiber probechanges.

The temperature adjustment means may include at least one of a heaterand a cooler.

Referring to FIG. 35, a heater 1121 and a temperature sensor 1123 may bedisposed inside the scanning module 110 according to still anotherembodiment of the present invention.

For example, as shown in FIG. 35, the heater 1121 may be installed alongthe inner wall of the housing H.

Also, as shown in FIG. 35, at least one temperature sensor 1123 may bedisposed inside the housing H.

In this case, the controller 130 may be set to control the operation ofthe heater 1121 when it is determined that the temperature detected bythe temperature sensor 1123 does not meet a preset criterion.

As an example, the controller 130 may control the operation of theheater 1121 to heat the inside of the scanning module 110 for apredetermined time by means of the heater 1121 when it is determinedthat the temperature detected by the temperature sensor 1123 is lowerthan the preset criterion.

On the other hand, the controller 130 may turn off the heater 1121 whenit is determined that the temperature detected by the temperature sensor1123 is higher than a preset criterion.

Meanwhile, the scanning module 110 according to still another embodimentof the present invention may allow the internal temperature condition ofthe optical fiber probe to be kept constant by a packaging method usinga heat-insulating material in addition to the above-describedtemperature adjustment means.

Accordingly, by controlling the internal temperature of the housing H tobe kept constant by means of the scanning module 110 according to stillanother embodiment of the present invention, the driving condition ofthe scanning module 110 may be kept constant.

4 Other Embodiments

With the scanning module 110 according to another embodiment of thepresent invention, by installing a magnet M inside the housing H, it ispossible to ascertain the actual movement of the optical fiber 1103.

For example, when the mass M attached to the distal end of the opticalfiber 1103 is a magnet, the magnet may be used to detect a positioncorresponding to the vibration of the optical fiber 1103.

In this case, the magnet may ascertain a position where the opticalfiber 1103 that performs Lissajous scanning is actually moved by using aforce transferred from the driving unit 1101.

Accordingly, with the scanning module 110 according to anotherembodiment of the present invention, it is possible to directlycalculate a phase difference that occurs while a driving signal appliedfrom the controller 130 to the scanning module 110 is being transferredto the scanning module 110.

Referring to FIG. 36, at least a first magnet MG1 and a second magnetMG2 may be disposed inside the scanning module 110 according to anotherembodiment of the present invention.

For example, the first magnet MG1 may be the mass M attached to thedistal end of the optical fiber 1103.

Also, for example, the second magnet MG2 may be configured to detectposition information for the first axis and the second axis of theoptical fiber 1103.

Alternatively, for example, a magnet for detecting position informationfor each of the first axis and the second axis of the optical fiber 1103may be separately disposed.

5 Phase Calibration in Image Generating Device

As described above, the image generating device is a device configuredto emit light and generate an image using returning light. For example,when light is output from the light-emitting unit 121, the light may beemitted to an object O through the scanning module 110. The lightreflected, scattered, refracted, and diffracted from the object O mayreturn to the image generating device and may be obtained by thelight-receiving unit 123. In this case, the controller 130 may obtainlight-receiving information indicating information regarding receivedlight.

Here, the controller 130 may control the light-emitting unit 121 tooutput light and may control the driving unit 1101 of the scanningmodule 110 to emit light to the object in a predetermined pattern.

In this case, a signal for controlling the driving unit 1101 may includean alternating current signal, which may be a signal having a frequencycomponent and a phase component to be applied to the driving unit 1101.Also, the signal for controlling the driving unit 1101 may have at leastone signal to be applied to the scanning module in each orthogonal axisdirection.

5.1 Cause of Phase Delay

The controller 130 may apply a driving signal to the driving unit 1101to operate the driving unit 1101. Also, the driving unit 1101 may outputa signal for controlling the scanning unit 1100 (hereinafter referred toas a scanning unit driving signal) and may drive the scanning unit 1100according to the output of the scanning unit driving signal. Also, thedriven scanning unit 1100 may emit light on the basis of an outputsignal for emitting light according to a predetermined pattern(hereinafter referred to as a scanning unit output signal).

The driving signal, the scanning unit driving signal, and the scanningunit output signal may be electrical signals, but the present inventionis not limited thereto. The signals may include a signal indicating amovement corresponding to the input of the signal. For example, when adriving signal is input to the driving unit 1101, the driving ormovement of the driving unit 1101 corresponding to the driving signalmay be expressed as a scanning unit driving signal. Also, when ascanning unit driving signal is input to the scanning unit 1100, thedriving or movement of the scanning unit 1100 corresponding to thescanning unit driving signal may be expressed as a scanning unit outputsignal. Also, the driving signal, the scanning unit driving signal, andthe scanning unit output signal may include signals having variouswaveforms (e.g., a sinusoidal waveform).

Also, the driving signal, the scanning unit driving signal, and thescanning unit output signal may be the same signal. Alternatively, thedriving signal, the scanning unit driving signal, and the scanning unitoutput signal may be signals with different phases.

FIG. 38 is a diagram comparatively showing the waveform of a signalbefore phase delay and the waveform of a signal after phase delay.

Referring to FIG. 38, the x-axis indicates time, and the y-axisindicates amplitude in the graph of FIG. 38. A pre-phase-delay signal5000 and a post-phase-delay signal 5001 may indicate signals having thesame amplitude and the same waveform. However, the present invention isnot limited thereto. The pre-phase-delay signal 5000 and thepost-phase-delay signal 5001 may have different amplitudes or waveforms.Alternatively, even in the pre-phase-delay signal 5000 or thepost-phase-delay signal 5001, the same amplitude or waveform may notalways appear over time.

Also, the post-phase-delay signal 5001 may represent a signal with adelayed phase compared to the pre-phase-delay signal 5000, and thepre-phase-delay signal 5000 and the post-phase-delay signal 5001 mayhave different phases. In FIG. 38, the phase difference between thepre-phase-delay signal 5000 and the post-phase-delay signal 5001 isshown as being constant at every time point. However, the presentinvention is not limited thereto, and the phase difference between thepre-phase-delay signal 5000 and the post-phase-delay signal 5001 maydiffer at every time point.

Also, the pre-phase-delay signal 5000 and the post-phase-delay signal5001 may be applied to all of the above-described driving signals,scanning unit driving signal, and scanning output signal.

According to an embodiment, the driving signal and the scanning unitdriving signal may have different phases. For example, when the drivingunit 1101 is driven by receiving a driving signal, energy including heator sound may be emitted from the driving unit 1101, and thus the phaseof the driving signal and the phase of the scanning unit driving signalmay differ from each other. Alternatively, when the driving unit 1101 isdriven by receiving a driving signal, the structure (or shape) of thedriving unit 1101 may be deformed, and thus the phase of the drivingsignal and the phase of the scanning unit driving signal may differ fromeach other. Here, the deformation of the structure of the driving unit1101 may mean that the structure of the driving unit 1101 is changed bybeing driven when a driving signal is input. For example, the change ofthe structure of the driving unit 1101 may include extension orcontraction of the driving unit 1101 along with the driving of thedriving unit 1101. However, the present invention is not limitedthereto, and the structure of the driving unit 1101 may be changed dueto an external cause in addition to the input of the driving signal.

According to another embodiment, the scanning unit driving signal andthe scanning unit output signal may have different phases. For example,when the scanning unit 1100 is driven by receiving a scanning unitdriving signal, energy including heat or sound may be emitted from thescanning unit 1100, and thus the phase of the scanning unit drivingsignal and the phase of the scanning unit output signal may differ fromeach other. Alternatively, when the scanning unit 1100 is driven byreceiving a scanning unit driving signal, the structure (or shape) ofthe scanning unit 1100 may be deformed, and thus the phase of thescanning unit driving signal and the phase of the scanning unit outputsignal may differ from each other. Here, the deformation of thestructure of the scanning unit 1100 may mean that the structure of thescanning unit 1100 is changed by being driven when a scanning unitdriving signal is input. For example, the change of the structure of thescanning unit 1100 may include extension or contraction of the scanningunit 1100 along with the driving of the scanning unit 1100. However, thepresent invention is not limited thereto, and the structure of thedriving unit 1101 may be changed due to an external cause in addition tothe input of the scanning unit driving signal.

5.2 Method of Finding Phase Delay and Method of Calibrating Phase

According to an embodiment for finding a phase delay, a reference imagemay be predetermined, and the reference image may be used to determine aphase delay. As an example, the predetermined reference image may be acircular pattern, but the present invention is not limited thereto.Thus, by comparing an image obtained by the controller 130 to thereference image, the degree of the phase delay may be ascertained.

Referring to FIG. 39, the image shown in (a) indicates a phase-delayedlow-resolution image, and the image shown in (b) indicates aphase-calibrated image of which a delayed phase is calibrated, which isa high-resolution image.

The controller 130 may allow the phase of a post-phase-delay signal tobe calibrated in order to obtain the image shown in (b) of FIG. 39instead of the image shown in (a) of FIG. 39.

According to an embodiment, the controller 130 may obtain aphase-calibrated image of which a delayed phase is calibrated by using aphase adjusted through the input unit 140.

As an example, the input unit 140 may adjust a frequency component or aphase component of a signal used for the controller 130 to control thedriving unit 1101 or may adjust both of the frequency component and thephase component. However, the present invention is not limited thereto.

In detail, the phase of the driving signal may be adjusted through theinput unit 140. When the phase of the driving signal is adjusted, thecontroller 130 may obtain a high-resolution image of which a phase iscalibrated by adjusting the phase component instead of thelow-resolution image caused by the post-phase-delay signal. According toanother embodiment, instead of obtaining a phase through the input unit140, the controller 130 may obtain a phase-calibrated image of which adelayed phase is calibrated by automatically adjusting the phase. Inthis case, the phase of the driving signal is not controlled using theinput unit 140, but the controller 130 may automatically calibrate thephase component of the driving signal. In detail, when the controller130 automatically calibrates the phase component of the signal forcontrolling the driving unit 1101, an algorithm may be used to calibratethe phase component. The phase calibration using the algorithm will bedescribed below.

6 Initial Phase Calibration

The image generating device may need to initially calibrate a phase inorder to calibrate the phase using an algorithm. However, the presentinvention is not limited thereto, and even when the phase is calibratedthrough the input unit 140, it may be necessary to initially calibratethe phase. For example, when the phase is calibrated using thealgorithm, an initial image of which a phase is not calibrated may havea large delay in phase. Also, when a phase is initially calibrated, aphase value to be adjusted by the controller 130 may be small.Accordingly, it is possible to reduce the time for performing the phasecalibration, and it is also possible to more accurately calibrate thephase.

In detail, when the phase is initially calibrated, the range of thephase to be adjusted through the input unit 140 may be reduced. Also,when the phase is calibrated using the algorithm, the amount ofcalculation required for even the phase value to be calibrated throughthe initial phase calibration can be reduced.

For convenience of description, the initial phase calibration may bedefined as a phase calibration method other than the phase calibrationusing the following algorithm. For example, the initial phasecalibration may include a phase calibration using the mounting device5200, a phase calibration using a cut-off filter, and a phasecalibration using a micropattern forming unit 5100, which will bedescribed below. In addition, various phase calibration methods may beincluded in the initial phase calibration.

According to an embodiment, when an object O is scanned, the phasecalibration may be performed through the input unit 140 after theinitial phase calibration, or the phase calibration may be performedusing the following algorithm. Also, according to another embodiment,after the phase calibration using the algorithm is performed, theinitial phase calibration may be performed. Then, the phase calibrationusing the algorithm may be performed again. It will be appreciated thatthe present invention is not limited thereto, and the initial phasecalibration and the phase calibration using the algorithm may beperformed at the same time.

Also, according to another embodiment, an image may be obtained byperforming only the initial phase calibration without performing thephase calibration using the algorithm.

A device and method for the initial phase calibration will be describedbelow.

6.1 Phase Calibration Using Lens Module 1200

The initial phase may be calibrated using the lens module 1200 that maybe positioned at one end of the scanning unit 1100. For example, byproviding a pattern onto the lens module 1200 positioned at one end ofthe scanning unit 1100, the initial phase may be calibrated using thepattern as the reference image. Alternatively, by providing a filtercapable of being mounted on the lens module 1200 and on one end of thescanning unit 1100, the initial phase may be calibrated using thefilter.

6.1.1 Phase Calibration using Micropattern Forming Unit 5100

FIG. 40 is a diagram showing a micropattern forming unit 5100 thatexhibits on a path of light emitted in a predetermined pattern(hereinafter referred to as a light pattern) when one element of thescanning module 110 including the lens module 1200 is patterned.

FIG. 40 shows a pattern in which light is emitted in the case of aLissajous pattern. However, the present invention is not limitedthereto, and the pattern in which light is emitted may include varioustypes of scanning patterns including a spiral pattern or a rasterpattern. Also, the micropattern forming unit 5100 shown in FIG. 40 isrepresented by characters. However, the present invention is not limitedthereto, and the micropattern forming unit 5100 may include a shape orthe like which may be used as the reference image.

Referring to FIG. 40, the light pattern may be formed in a squareregion. However, the present invention is not limited thereto, and thelight pattern may be formed in areas of various shapes. The lightpattern may be emitted toward the object O when the scanning unit 1100is driven, and the micropattern forming unit 5100 may not changeaccording to the light pattern.

Here, when the scanning module 110 is scanning the object O, amicropattern, which is an image corresponding to the micropatternforming unit 5100, may appear on an image obtained by the controller130.

Also, the micropattern forming unit may be disposed at various positionsin the scanning module 110. In detail, the micropattern forming unit maybe positioned on the lens module 1200. However, the present invention isnot limited thereto, and the micropattern forming unit may be positionedon the scanning unit 1100. Alternatively, the micropattern forming unitmay be predetermined on a separate structure, and the structure may becoupled to one end of the scanning module 110 and used to calibrate theinitial phase. For convenience of description, the following descriptionassumes that the micropattern forming unit 5100 is positioned on thelens module 1200.

According to an embodiment, the micropattern forming unit 5100 presenton the lens module 1200 may be present at a position through which thelight pattern has passed. When the scanning module 110 is being scanned,a certain micropattern may be provided regardless of the shape of theobject O. Thus, by using the micropattern as the reference image, theinitial phase calibration may be performed such that the micropattern ofthe image obtained by the controller 130 can coincide with themicropattern appearing in the original micropattern forming unit 5100.

Here, the micropattern of the obtained image that coincides with themicropattern appearing in the micropattern forming unit 5100 may meanthat when the controller 130 obtains light-receiving information on thebasis of the light returning from the object O, information of a pixelof a portion of the image obtained by the controller 130 where themicropattern is expected to appear corresponds to information of a pixelcorresponding to the micropattern provided by the micropattern formingunit 5100 at a certain level or more.

However, in order for the controller 130 to obtain an imagecorresponding to the micropattern forming unit 5100 at a positionthrough which the light pattern has passed when light is emitted fromthe scanning unit 1100, the micropattern forming unit 5100 may be madeof a material capable of absorbing or reflecting the emitted light orcapable of exhibiting fluorescence due to the emitted light.

In detail, when the micropattern forming unit 5100 is made of a materialcapable of absorbing light emitted from the scanning unit 1100, themicropattern forming unit 5100 may absorb the emitted light, and nolight may return from the micropattern forming unit 5100 due to theabsorption of the light. Here, the absorption of light by themicropattern forming unit 5100 may mean that the micropattern formingunit 5100 absorbs a specific wavelength band of light and thus the lightcannot return from the micropattern forming unit 5100. Accordingly, whenthe controller 130 generates an image using a specific wavelength oflight, the specific wavelength is absorbed, and a wavelengthcorresponding to the shape of the micropattern of the micropatternforming unit 5100 cannot be obtained. Thus, light and shade may occur inthe portion of the obtained image corresponding to the micropattern.Accordingly, the portion of the obtained image corresponding to themicropattern is obtained, and thus phase calibration may be performedsuch that the portion of the obtained image corresponding to themicropattern can coincide with the micropattern of the micropatternforming unit 5100.

Alternatively, when the micropattern forming unit 5100 is made of amaterial capable of reflecting light emitted from the scanning unit1100, the micropattern forming unit 5100 may reflect the emitted light,and all of the emitted light may return from the micropattern formingunit 5100. Here, the reflection of light by the micropattern formingunit 5100 may mean that a specific wavelength band of light is reflectedand thus light of the same wavelength as that of the light that has beenemitted from the micropattern forming unit 5100 is returning.Accordingly, when the controller 130 generates an image using a specificwavelength of light, the wavelength corresponding to the micropatternforming unit 5100 obtained by the controller 130 may not be the specificwavelength for generating the image. Thus, light and shade may occur ina portion of the obtained image corresponding to the micropattern of themicropattern forming unit 5100. Accordingly, the portion of the obtainedimage corresponding to the micropattern is obtained, and thus phasecalibration may be performed such that the portion of the obtained imagecorresponding to the micropattern can coincide with the micropattern ofthe micropattern forming unit 5100.

Alternatively, when the micropattern forming unit is made of a materialcapable of exhibiting fluorescence using emitted light, light returningfrom the micropattern forming unit 5100 may be fluorescent light. Here,the exhibition of fluorescent light by the micropattern forming unit5100 may mean that the micropattern forming unit 5100 absorbs theemitted light and generates light having a wavelength different fromthat of the absorbed light such that light of a specific wavelength isreturning from the micropattern forming unit 5100. Also, a materialcapable of emitting light having a wavelength of 405 nm, 488 nm, or 785nm may be used as the fluorescent material used in the micropatternforming unit 5100. Thus, when the controller 130 generates an imageusing light having a specific wavelength due to the fluorescentmaterial, the light of the wavelength corresponding to the micropatternforming unit 5100 may be obtained. Thus, light and shade may occur inthe portion of the obtained image corresponding to the micropattern.Accordingly, the portion of the obtained image corresponding to themicropattern shape is obtained, and thus phase calibration may beperformed such that the portion of the obtained image corresponding tothe micropattern can coincide with the micropattern of the micropatternforming unit 5100.

Here, the phase calibration may mean that the controller 130 obtains animage in which the micropattern appears and performs calibration suchthat the obtained image in which the micropattern appears corresponds tothe shape of the micropattern of the micropattern forming unit 5100 at apredetermined level or more. In detail, the micropattern shape of themicropattern forming unit 5100 may be obtained by the controller 130,and thus the controller 130 may compare a micropattern included in animage obtained by driving the scanning unit 1100 to the micropatternshape pre-obtained by the controller 130 to obtain the correspondingdegree. In this case, when the comparison result obtained by thecontroller 130 is less than or equal to the predetermined level, thecomparison may be performed again after the phase of the driving signalis changed. Also, when the comparison result obtained by the controller130 is greater than or equal to the predetermined level, the controller130 may obtain an image of the object O by using the changed drivingsignal as a phase value to be calibrated. In this case, the phase of thedriving signal may be changed using the input unit 140 on the controller130. However, the present invention is not limited thereto, and thephase may be automatically calibrated using the algorithm.

However, the phase calibration using the micropattern is not limited tothe initial phase calibration and can be performed while the object O isbeing scanned. 6.1.2 Phase Calibration Using Cut-off Filter FIG. 41 is adiagram showing that a corner of a light pattern on an element of thescanning module 110 including the lens module 1200 is cut off. Here, thecut-off may mean that a portion of the corner of the light pattern isformed of a material capable of absorbing or reflecting the light orexhibiting fluorescence due to the light and the image of the object Omay not be obtained at the portion of the corner.

Also, the cut-off filter may be positioned on the lens module 1200.However, the present invention is not limited thereto, and the cut-offfilter may be positioned on the scanning unit 1100. Alternatively, thecut-off filter may be present on a separate structure, and the structuremay be coupled to one end of the scanning module 110 and used tocalibrate the initial phase. For convenience of description, thefollowing description assumes that the cut-off filter is positioned onthe lens module 1200.

Also, as shown in FIG. 41, the cut-off filter is present on the cornerof the optical device. Thus, when light is emitted from the scanningunit 1100, the cut-off filter may absorb or reflect light or exhibitfluorescence at a portion where the density of the emitted light isincreased. Therefore, it is possible to prevent photo bleaching in whicha fluorescent material in the object O may be damaged when the intensityof the emitted light is increased or photo damaging in which the objectO itself may be damaged due to a high light intensity.

According to an embodiment, when the cut-off filter is made of amaterial capable of absorbing or reflecting light, the light-receivingunit 123 of an image generating module for generating an image using aspecific wavelength of light may not obtain light-receiving information.In detail, the light absorbed or reflected at the cut-off corner doesnot reach the light-receiving unit 123 and does not generatelight-receiving information. Thus, a pixel value corresponding to thecorner portion does not appear in the image obtained by the controller130, and the corner portion may be displayed as an unused area.

Alternatively, when the cut-off filter is made of a fluorescentmaterial, the light returning from the object O may be composed of aspecific wavelength that can be obtained by the light-receiving unit123. Accordingly, the light-receiving unit 123 may obtain fluorescenceat the cut-off corner as the light-receiving information, and thus apixel value corresponding to the corner portion may be obtained from theimage obtained by the controller 130 in the form of an unused area.

The image (a) of FIG. 42 is a diagram showing an unused areacorresponding to the cut-off filter in an image obtained when the phaseof a scanning unit driving signal or a scanning unit output signal isdelayed. The image (b) of FIG. 42 is a diagram showing an unused areacorresponding to the cut-off filter in an image obtained when the phaseof a scanning unit driving signal or a scanning unit output signal iscalibrated.

In detail, when the phase of the scanning unit driving signal or thescanning unit output signal is delayed compared to the phase of thedriving signal, an unused area corresponding to the cut-off may begenerated not in a place where the cut-off portion is originally presentas shown in the image (a) of FIG. 42 but in any space of the obtainedimage. Thus, when the unused area corresponding to the cut-off isgenerated not at the corner of the obtained image but in any space ofthe obtained image after the obtained image is checked, the phase of thescanning unit driving signal or the scanning unit output signal may bedelayed.

According to an embodiment, information regarding the unused area in theimage obtained by the controller 130 according to the cut-off filter maybe obtained by the controller 130. Also, when the scanning is performedusing the scanning module 110, the degree to which the unused area ispresent on the corner of the obtained image may be obtained by thecontroller 130. When the degree to which the unused area is present onthe corner, which is obtained by the controller 130, is less than orequal to a certain level, the degree to which the unused area is presenton the corner may be re-obtained by the controller 130 after the phaseof the driving signal is changed. In this case, when the degree to whichthe unused area is present on the corner, which is obtained by thecontroller 130, is greater than or equal to a certain level, thecontroller 130 may obtain the image of the object O using the adjustedphase of the driving signal as the phase value to be calibrated. Here,the phase of the driving signal may be changed using the input unit 140on the controller 130. However, the present invention is not limitedthereto, and the phase may be automatically calibrated using thealgorithm.

According to another embodiment, the phase of the driving signal of thephase-delayed image as shown in (a) of FIG. 42 may be calibrated usingthe input unit 140. In detail, when the image shown in (a) of FIG. 42 isobtained by the controller 130, the phase of the driving signal may beadjusted using the input unit 140. By adjusting the phase of the drivingsignal, the unused area generated in any space may be moved, and theunused area may be generated on the corner of the obtained image.Therefore, the phase-calibrated image as shown in (b) of FIG. 42 may beobtained by the controller 130.

According to another embodiment, the phase of the driving signal of thephase-delayed image as shown in (a) of FIG. 42 may be calibrated usingan algorithm for phase calibration, which will be described below.

6.2 Phase Calibration Using Mounting Device 5200 of Scanning Module 110

As described above, the scanning module 110 may scan the object O, andthe controller 130 may obtain an image corresponding to the scanning.

Here, the mounting device 5200 does not perform scanning on the objectO. When the scanning module 110 is not used, the mounting device 5200may be used to mount the scanning module 110. Also, the phase of thedriving signal may be calibrated by the mounting device 5200 on whichthe scanning module 110 is mounted.

According to an embodiment, a reference image may be provided to themounting device 5200 of the scanning module 110, and the phasecalibration may be performed on the basis of the reference image. Indetail, when the phases of the scanning unit driving signal and thescanning unit output signal are delayed, the phase of the driving signalmay be calibrated such that the image obtained by the controller 130 cancoincide with the reference image.

Here, the phase of the driving signal may be calibrated using the inputunit 140 on the controller 130 or using algorithm-based phasecalibration.

6.2.1 Structure of Mounting Device 5200 of Scanning Module 110

Referring to FIG. 43, the mounting device 5200 may include anaccommodation unit 5210, a coupling unit 5220, a reference pattern unit5230, or an adjustment unit 5240. Here, the accommodation unit 5210 ofthe mounting device 5200 of the scanning module 110 may accommodate thescanning module 110. For example, the accommodation unit 5210 mayinclude a housing for accommodating the scanning module 110. Also, thecoupling unit 5220 of the mounting device 5200 of the scanning module110 may couple the scanning module 110 accommodated in the accommodationunit 5210 to the accommodation unit 5210 so that the scanning module 110accommodated in the accommodation unit 5210 is prevented from fallingout of the accommodation unit 5210 or so that the scanning module 110 isfixed at a specific position of the accommodation unit 5210. Also, thereference pattern unit 5230 of the mounting device 5200 of the scanningmodule 110 may provide a reference image so that the controller 130 cancalibrate the phase of the driving signal while the scanning module 110is mounted on the mounting device 5200. Also, when the lens module 1200on the scanning module 110 is not focused, the adjustment unit 5240 ofthe mounting device 5200 of the scanning module 110 may provide anelement for performing focusing at the mounting device 5200 while thescanning module 110 is mounted on the mounting device 5200 of thescanning module 110. The accommodation unit 5210, the coupling unit5220, the reference pattern unit 5230, and the adjustment unit 5240 willbe described in detail below.

6.2.1.1 Accommodation Unit 5210 of Mounting Device 5200

FIG. 44 is a diagram showing that the scanning module 110 isaccommodated in the image generating device.

According to an embodiment, as shown in FIG. 44, the accommodation unit5210 of the mounting device 5200 on which the scanning module 110 can bemounted may be provided to the image generating device. In detail, thescanning module 110 may be mounted on the accommodation unit 5210 of themounting device 5200 present on the image generating device of FIG. 44.Also, there is no limitation on the position on the image generatingdevice shown in FIG. 44.

According to another embodiment, the accommodation unit 5210 of themounting device 5200 on which the scanning module 110 can be mounted maybe present at a position physically different from that of the imagegenerating device. In this case, the accommodation unit 5210 of themounting device 5200 present at a position different from that of theimage generating device may be pre-connected to the image generatingdevice, and thus the mounting device 5200 may be controlled through thecontroller 130 of the image generating device.

Also, the accommodation unit 5210 may accommodate the entirety of thescanning module 110. However, the present invention is no limitedthereof, and the accommodation unit 5210 may accommodate only a portionof an element for emitting light included in the scanning module 110 sothat the phase delay of the driving signal, the scanning unit drivingsignal, or the scanning unit output signal can be calibrated.

6.2.1.2 Coupling unit 5220 of Mounting Device 5200

FIG. 45 is a diagram showing that the scanning module 110 is mounted onthe mounting device 5200. Also, FIG. 46 is a diagram showing theaccommodation unit 5210 of the mounting device 5200 when viewed from theentrance thereof.

According to an embodiment, a coupling member 5250 may be provided onthe scanning module 110 as shown in FIG. 45. Here, the coupling membermay be coupled to the coupling unit 5220 of the mounting device 5200,and thus the scanning module 110 may be coupled to the mounting device5200 at a certain angle.

In detail, the coupling unit 5220 of the mounting device 5200 and thecoupling member may be formed in the same shape so that the scanningmodule 110 and the mounting device 5200 can be coupled to each other, orthe coupling unit 5220 may be present in the shape including the shapeof the coupling member. For example, when the coupling member has aquadrangular shape, the coupling unit 5220 of the mounting device 5200may have a quadrangular shape capable of accommodating the quadrangularshape of the coupling member or may have a shape that circumscribes thequadrangular shape of the coupling member. However, the presentinvention is not limited thereto, and the coupling unit 5220 of themounting device 5200 may have a shape in which the coupling unit 5220 ofthe mounting device 5200 is coupled to the coupling member, includingthe shape of the coupling member. Also, the coupling member of thescanning module 110 and the coupling unit 5220 of the mounting device5200 may be various members with a coupling force so as to couple thecoupling member and the coupling unit 5220 to each other. For example,the coupling member of the scanning module 110 and the coupling unit5220 of the mounting device 5200 may be provided as magnetic members.Since there is a magnetic force between the coupling member and thecoupling unit 5220, the scanning module 110 may be coupled to a specificposition of the accommodation unit 5210 when the scanning module 110 iscoupled to the accommodation unit 5210 of the mounting device 5200.Also, since there is a magnetic force, the coupling member and thecoupling unit 5220 may be automatically coupled to each other at thespecific position.

6.2.1.3 Reference Pattern Unit 5230 of Mounting Device 5200

The reference pattern unit 5230 may be provided to the mounting device5200 such that the initial phase calibration can be performed by thecontroller 130. Here, the reference pattern unit 5230 may be provided ina space of the mounting device 5200. However, for convenience ofdescription, the following description assumes that the referencepattern unit 5230 is provided on a lower end portion of the mountingdevice 5200. Here, when the scanning module 110 is mounted on themounting device 5200, the lower end portion of the mounting device 5200may be the bottom surface of the accommodation unit 5210 that is presenton an extension line in a direction in which light is emitted by thescanning module 110.

FIG. 47 is a diagram of the reference pattern unit 5230 when viewed fromthe top. In detail, when the scanning module 110 is mounted on themounting device 5200, the scanning module 110 may emit light toward thereference image 5231 of the reference pattern unit 5230 provided on thelower end of the mounting device 5200 and may obtain an image usingreturning light. Here, when the phase of the scanning unit drivingsignal or the scanning unit output signal is delayed, the obtained imagemay be a phase-delayed image. In this case, the controller 130 maycalibrate the phase of the driving signal, the phase of the scanningunit driving signal, or the scanning unit output signal such that theobtained image can coincide with the reference image 5231.

Referring to FIG. 47, the reference image 5231 may be one or morecircular patterns in order to always provide a certain imageirrespective of an angle at which the scanning module 110 is mounted onthe mounting device 5200. However, the present invention is not limitedthereto, and the reference image may be a predetermined reference image5231. In detail, when the coupling unit 5220 and the coupling member arenot present, the scanning module 110 may not be mounted at apredetermined position when the scanning module 110 is mounted on themounting device 5200. Accordingly, even when the scanning module 110 isnot mounted at a predetermined position, the reference image 5231 may bea circular pattern so that the initial phase calibration can beperformed.

According to an embodiment, the reference image 5231 may be made of amaterial capable of absorbing light emitted by the scanning unit 1100.In detail, when the reference image 5231 is made of a material capableof absorbing light emitted by the scanning unit 1100, the referenceimage 5231 may absorb the emitted light, and no light may return fromthe reference image 5231. Here, the absorption of light by the referenceimage 5231 may mean that the reference image 5231 absorbs a specificwavelength band of light and thus the light cannot return from thereference image 5231. Accordingly, when the controller 130 generates animage using a specific wavelength of light, a wavelength correspondingto the reference image 5231 cannot be obtained. Thus, light and shademay occur in the portion of the obtained image corresponding to thereference image 5231. Therefore, the portion of the obtained imagecorresponding to the reference image 5231 may be obtained, and thus thephase of the obtained image may be calibrated.

According to another embodiment, the reference image 5231 may be made ofa material capable of reflecting light emitted by the scanning unit1100. In detail, when the reference image 5231 is made of a materialcapable of reflecting light emitted by the scanning unit 1100, thereference image 5231 may reflect the emitted light, and all of theemitted light may return from the reference image 5231. Here, thereflection of light by the reference image 5231 may mean that thereference image 5231 reflects a specific wavelength band of light andlight having the same wavelength as that of the light having beenemitted returns from the reference image 5231. Accordingly, when thecontroller 130 generates an image using a specific wavelength of light,a wavelength corresponding to the reference image 5231 may not be aspecific wavelength. Thus, light and shade may occur in the portion ofthe obtained image corresponding to the reference image 5231. Therefore,the portion of the obtained image corresponding to the reference image5231 may be obtained, and thus the phase of the obtained image may becalibrated.

According to another embodiment, the reference image 5231 may be made ofa material capable of exhibiting fluorescence. In detail, when thereference image 5231 is made of a material capable of exhibitingfluorescence using emitted light, light returning from the referenceimage 5231 may be fluorescent light. Here, the exhibition of fluorescentlight by the reference image 5231 may mean that the reference image 5231absorbs the emitted light and generates light having a wavelengthdifferent from that of the absorbed light such that light of a specificwavelength returns from the reference image 5231. Accordingly, when thecontroller 130 generates an image using a specific wavelength caused bya fluorescent material, a wavelength corresponding to the referenceimage 5231 cannot be obtained. Thus, light and shade may occur in theportion of the obtained image corresponding to the reference image 5231.Therefore, the portion of the obtained image corresponding to thereference image 5231 may be obtained, and thus the phase of the obtainedimage may be calibrated.

Here, the phase calibration may mean that the controller 130 obtains animage in which the reference image 5231 appears and performs calibrationsuch that the image in which the reference image 5231 appears and thereference image 5231 which is present on the mounting device 5200correspond to each other at a predetermined level or more. In detail,the reference image 5231 of the mounting device 5200 may be obtained bythe controller 130, and thus the controller 130 may compare a referenceimage 5231 included in an image obtained by driving the scanning unit1100 to the reference image 5231 pre-obtained by the controller 130 toobtain the corresponding degree. In this case, when the comparisonresult obtained by the controller 130 is less than or equal to thepredetermined level, the comparison may be performed again after thephase of the driving signal is changed. Also, when the comparison resultobtained by the controller 130 is greater than or equal to thepredetermined level, the controller 130 may obtain an image of theobject O by using the changed driving signal as a phase value to becalibrated. In this case, the phase of the driving signal may be changedusing the input unit 140 on the controller 130. However, the presentinvention is not limited thereto, and the phase may be automaticallycalibrated using the algorithm.

6.2.1.3.1 Structure of Reference Pattern Unit 5230

In order to provide a reference image 5231 matching the focal length ofthe lens module 1200 on the scanning module 110, the reference patternunit 5230 may be provided with a structure matching the focal length.

FIG. 48 is a diagram showing that the reference image 5231 on thereference pattern unit 5230 is present in a transparent structure.

According to an embodiment, referring to FIG. 48, an image may bepresent in an optical transmission structure 5235 in order to providethe reference image 5231 to match the focal length of the lens module1200. In detail, the optical transmission structure 5235 may be made ofglass or transparent plastic. However, the present invention is notlimited thereto, and any material capable of transmitting light may beused as the material of the optical transmission structure 5235. Also,here, the reference image 5231 present in the optical transmissionstructure 5235 may be provided to match the focal length of the lensmodule 1200, and the size of the reference image 5231 may decrease asthe focal length increases. However, the present invention is notlimited thereto, and the size of the reference image 5231 may increaseas the focal length increases or may be constant. When the opticaltransmission structure 5235 is shown from the upper side in which lightis emitted, the reference image 5231 varying by depth may be provided asshown in FIG. 47.

According to another embodiment, referring to FIG. 49, the referenceimage 5231 may be present in a concave structure 5237 in order toprovide the reference image 5231 to match the focal length of the lensmodule 1200. In detail, as the depth of the concave structure 5237increases, the size of the reference image 5231 provided in the concavestructure 5237 may decrease. Thus, a smaller reference image 5231 may beprovided as the focal length becomes deeper. Here, the reference image5231 may be drawn around the concave structure 5237, and the referenceimage 5251 drawn around the concave structure 5237 is smaller in size asthe depth increases in the concave structure 5237. When the concavestructure 5237 is shown from the upper side in which light is emitted,the reference image 5231 having a size varying by depth may be providedas shown in FIG. 47.

6.2.1.3.2 Case in which Reference Image 5231 is Made of FluorescentMaterial

The controller 130 may obtain an image using light of a specificwavelength. Thus, when the reference image 5231 is provided using afluorescent material, the controller 130 may obtain light-receivinginformation corresponding to the reference image 5231.

According to an embodiment, when the reference image 5231 is made of afluorescent material, the fluorescent material may include IcG, 5-ALA,or Fna. However, the present invention is not limited thereto, and anymaterial capable of exhibiting fluorescence due to light emission may beused. However, when a fluorescent material is used for the referenceimage 5231, fluorescence may not be exhibited due to the continued useof the fluorescent material. Thus, it may be necessary to supplement thefluorescent material.

Here, in order to supplement the fluorescent material to be used for thereference image 5231, a cartridge that can additionally provide afluorescent material may be provided. The cartridge may be inserted intoor removed from a lower end of the mounting device 5200. However, thepresent invention is not limited thereto, and the cartridge may bepresent on an upper portion or side surface of the mounting device 5200or outside the mounting device 5200 to provide the fluorescent materialto the reference image 5231. For convenience of description, thefollowing description assumes that the cartridge is present on the lowerend portion of the mounting device 5200.

In detail, the cartridge may be a structure including a fluorescentmaterial therein, and the fluorescent material may be provided for thereference image 5231 to obtain a fluorescence image caused by thefluorescent material of the reference image 5231 when light is emittedto the scanning module 110. Also, when the reference image 5231 does notexhibit fluorescence due to light emission (e.g., including that thefluorescent material is degraded by photo bleaching caused by lightemission), a cartridge that is provided at the lower end of the mountingdevice 5200 may be removed therefrom, and a new cartridge containing afluorescent material capable of exhibiting fluorescence may be insertedto the lower end portion of the mounting device 5200. However, thepresent invention is not limited thereto, and the cartridge may have astructure provided outside the mounting device 5200 to continuouslysupply the fluorescent material to the reference image 5231.

6.2.1.4 Adjustment Unit 5240 of Mounting Device 5200

The mounting device 5200 may include an adjustment unit 5240 in order toprovide the reference image 5231 matching the focal length of the lensmodule 1200 of the scanning module 110. Here, the adjustment unit 5240may control the position of the reference pattern unit 5230 to be movedclose to or far away from the lens module 1200 of the scanning module110 in order to provide the reference pattern unit 5230 in which thereference image 5231 is provided to match the focal length.

In this case, when the reference image 5231 is present at a position notmatching the focal length of the lens module 1200 of the scanning module110, the image obtained by the controller 130 may not match thereference image 5231. Thus, the adjustment unit 5240 may be necessary toadjust the reference pattern unit 5230 in which the reference image 5231is present according to the focal length of the lens module 1200.

The image (a) of FIG. 50 is a diagram showing that the reference patternunit 5230 is adjusted toward the entrance of the mounting device 5200 sothat the reference pattern unit 5230 is coupled to the adjustment unit5240 at the lower end portion of the mounting device 5200 to adjust thefocal length in order to provide the reference image 5231 matching thefocal length of the lens module 1200. The image (b) of FIG. 50 is adiagram showing that the reference pattern unit 5230 present at thelower end of the mounting device 5200 is moved toward the lower endportion of the mounting device 5200 in order to provide the referenceimage 5231 matching the focal length of the lens module 1200.

According to an embodiment, the adjustment unit 5240 may be present inorder to adjust the distance of the reference pattern unit 5230 presentat the lower end portion of the mounting device 5200. In detail, theadjustment unit 5240 may be present on the lower end of the mountingunit. However, the present invention is not limited thereto, and theadjustment unit 5240 may be present outside the mounting device 5200 toadjust the position of the reference pattern unit 5230. Although notshown, an adjustment module may be included in the adjustment unit 5240,and the adjustment module may be controlled by a user. According to theuser's control, the adjustment module may adjust the reference image5231 to match the focal length of the lens module 1200. Here, theprovision of the reference image 5231 to match the focal length of thelens module 1200 may mean that the controller 130 compares an obtainedimage to the reference image 5231 and then moves the position of thereference pattern unit 5230 such that the obtained image can coincidewith the reference image 5231 well.

According to another embodiment, the adjustment unit 5240 mayautomatically adjust the position of the reference pattern unit 5230such that the reference image 5231 present on the reference pattern unit5230 can be provided to match the focal length of the lens module 1200.In detail, the adjustment unit 5240 present at the lower end portion ofthe mounting device 5200 may be provided with an electrical ormechanical motor, and the motor may adjust the position of the referencepattern unit 5230 such that the reference pattern unit 5230 can coincidewith the focal length of the lens module 1200. Here, in order to adjustthe position of the reference pattern unit 5230 such that the referencepattern unit 5230 can coincide with the focal length of the lens module1200, a controller for controlling the reference pattern unit 5230 maybe present on the mounting device 5200 although not shown. Also, themounting device 5200 may include a communication unit for communicatingwith the image generating device, and the communication unit maycommunicate with the controller 130 of the image generating device in awired or wireless communication manner. Although not shown, acommunication unit of the controller 130 of the image generating devicemay obtain information regarding the position of the reference patternunit 5230 from the controller of the mounting device 5200 and maycompare an image obtained by the scanning module 110 emitting light tothe reference image 5231. Also, when the comparison result between theobtained image and the reference image 5231 is that no image matchingthe focal length of the lens module 1200 is obtained, the controller 130of the image generating device may adjust the adjustment unit 5240 ofthe mounting device 5200 through the communication unit, and theposition of the reference pattern unit 5230 may be moved by theadjustment unit 5240 to coincide with the focal length of the lensmodule 1200.

6.3 Initial Phase Calibration Method by Mounting Device 5200

FIG. 51 is a diagram for describing an initial phase calibration methodusing the reference image 5231 present in the mounting device 5200.

Referring to FIG. 51, the initial phase calibration method may beperformed by the controller 130. Also, the initial phase calibrationmethod may include emitting light from the scanning module 110 to thereference pattern unit 5230 (S5000), obtaining an image using lightreturning from the reference pattern unit 5230 (S5010), comparing theobtained image to the reference image 5231 (S5020), and calibrating thephase of a driving signal on the basis of a result of the comparison(S5030).

When light is emitted from the scanning module 110 to the referencepattern unit 5230 (S5000), the controller 130 may apply a driving signalto the driving unit 1101. Also, the driving unit 1101 receives thedriving signal and applies, to the scanning unit 1100, a scanning unitdriving signal for driving the scanning unit 1100. When the scanningunit driving signal is received, the scanning unit 1100 may emit lightto an object O according to the scanning unit driving signal.

In this case, when phase calibration is not performed, a phase delay mayoccur between the driving signal and the scanning unit driving signal orthe scanning unit output signal. Thus, before the scanning module 110 isseparated from the mounting device 5200 to scan the object O, the phasedelay may need to be calibrated. Therefore, for convenience ofdescription, the calibration of the phase delay will be described as theinitial phase calibration.

Here, when the initial phase calibration is not performed, the scanningof the object O is performed. When the phase calibration using thealgorithm is performed, the calibration may be made with a phase otherthan an actual delayed phase value between the driving signal and thescanning unit output signal. Thus, when the initial phase calibration isperformed while the scanning module 110 is not used, the time fordiscovering a phase to be calibrated during the scanning may beshortened, and also the controller 130 may directly obtain an image ofthe object O.

When the controller 130 obtains the image (S5010) and the controller 130compares the obtained image to the reference image 5231 (S5020), thescanning module 110 may emit light toward the reference pattern unit5230 while the scanning module 110 is mounted on the mounting device5200. In detail, when light is emitted toward the reference pattern unit5230 while the scanning module 110 is mounted, the light may continue tobe emitted toward the reference pattern unit 5230 while the scanningmodule 110 is mounted. However, the present invention is not limitedthereto, and the light may be emitted every predetermined period, andthe initial phase calibration may be performed. Also, when the degree towhich a calibrated image obtained by the controller 130 according to theinitial phase calibration coincides with the reference image 5231 isless than or equal to a predetermined level, light may continue to beemitted such that an image calibrated at the predetermined level or morecan coincide with the reference image 5231. Also, when light is emittedevery predetermined period to perform the initial phase calibration, anytime may be set every predetermined period. However, the presentinvention is not limited thereto, and the initial phase calibration maycontinue to be performed while the scanning module 110 is driven. Indetail, when the image generating device is operating, the scanningmodule 110 may also be operating. Here, when the image generating deviceis not operating, the scanning module 110 may also stop operating. Thus,the phase delay value when the scanning module 110 starts to operateagain may not be the same as the phase delay value of the scanning unitoutput signal before the scanning module 110 stops operating.

Accordingly, performing the initial phase calibration by emitting lightevery predetermined period may be possible until the scanning module 110stops operating when the scanning module 110 continues to operate as theimage generating device is operated.

Here, the image obtained by the controller 130 coinciding with thereference image 5231 may mean that when light-receiving informationbased on light returning from the object O is obtained by the controller130, information of a pixel of a portion of the image obtained by thecontroller 130 where the reference image 5231 is predicted to appearcorresponds to information of a pixel corresponding to the referenceimage 5231 at a certain level or more.

Thus, when the phase of the driving signal, the scanning unit drivingsignal, or the scanning unit output signal is initially delayed, theimage obtained by the controller 130 using the light that is emittedfrom the scanning module 110 and that returns from the reference patternunit 5230 may not coincide with the reference image 5231. Thus, theinitial phase calibration may be performed so that the image of thereference pattern unit 5230 and the image obtained by the controller 130can coincide with each other.

When the phase of the driving signal is calibrated (S5030), the phase ofthe driving signal may be calibrated using the phase value as foundabove to be calibrated. For example, when the reference image 5231 doesnot coincide with the image obtained by the controller 130, the phase ofthe driving signal, the scanning unit driving signal, or the scanningunit output signal may be adjusted such that the image obtained by thecontroller 130 can coincide with the reference image 5231 using theinput unit 140 of the controller 130 in order to perform the initialphase calibration method.

According to another embodiment, when the reference image 5231 does notcoincide with the image obtained by the controller 130, the delayedphase of the driving signal, the scanning unit driving signal, or thescanning unit output signal may be calibrated by the controller 130using the algorithm in order to perform the initial phase calibration.The phase calibration using the algorithm will be described below.

7 Phase Calibration Using Standard Deviation

The phase of the driving signal and the phase of the scanning unitdriving signal or the scanning unit output signal may be different fromeach other when the controller 130 applies the driving signal to thedriving unit 1101. Also, as described with reference to FIG. 38, thepre-phase-delay signal 5000 may be the driving signal, and thepost-phase-delay signal 5001 may be the scanning unit driving signal orthe scanning unit output signal.

In detail, light emitted by the scanning unit 1100 according to thescanning unit output signal may return from the object O due to aninteraction between the light and the object O, including reflection,scattering, refraction, and diffraction, and the light-receiving unit123 may obtain the light-receiving information by using the returninglight. The controller 130 may obtain an image using the light-receivinginformation.

In this case, when an image is generated using the driving signal andthe light-receiving information obtained by the controller 130, an imagehaving a clear resolution may not be obtained due to a phase delaybetween the driving signal and the scanning unit output signal. Thus,when the phase delay of the driving signal is calibrated usinglight-receiving information obtained during scanning, real-time phasecalibration may be possible, and the controller 130 may obtain a clearresolution image. A method of obtaining and calibrating a phase delayusing the light-receiving information in order to calibrate the phase ofthe driving signal according to the phase delay value will be describedbelow.

7.1 Image Acquisition Scheme of Controller 130

FIG. 52 is a diagram showing information to be stored in order for thecontroller 130 to obtain an image using the driving signal and theobtained light-receiving information. Here, a position corresponding toa first signal may refer to a position corresponding to a signal that isapplied in the first axis direction among driving signals. Also, aposition corresponding to a second signal may refer to a positioncorresponding to a signal that is applied in the second axis directionorthogonal to the first axis among signals for controlling the drivingunit 1101. Also, an acquisition signal value may be a signal includingthe light-receiving information obtained by the light-receiving unit123. However, the present invention is not limited thereto, and theinformation regarding returning light may be included in the acquisitionsignal value.

In detail, the first axis direction may refer to the x-axis in theCartesian coordinate system, and the second axis direction may refer tothe y-axis in the Cartesian coordinate system. However, the presentinvention is not limited thereto, and any coordinate system for emittinglight to an object O using a scanning pattern may be included, such asthe polar coordinate system. For convenience of description, thefollowing description assumes that the first signal is applied in thefirst axis direction corresponding to the x-axis in the Cartesiancoordinate system and the second signal is applied to the second axisdirection corresponding to the y-axis in the Cartesian coordinatesystem. Accordingly, the position corresponding to the first signal mayrefer to an x-axis coordinate value of the image obtained by thecontroller 130, and the position corresponding to the second signal mayrefer to a y-axis coordinate value of the image obtained by thecontroller 130. Here, the position corresponding to the first signal andthe position corresponding to the second signal may indicate coordinatevalues varying over time.

Also, as described above, the first axis direction and the second axisdirection may be the same as the first axis direction and the secondaxis direction when the scanning unit 1100 is driven in the scanningmodule 110. The image obtained by the controller 130 may include aplurality of pixels. Therefore, the position corresponding to the firstsignal and the position corresponding to the second signal, that is, thex-axis coordinate value and the y-axis coordinate value of the imageobtained by the controller 130 may indicate position information of theplurality of pixels of the image obtained by the controller 130.

According to an embodiment, the position corresponding to the drivingsignal input through the controller 130 in order to drive the drivingunit 1101 may be predetermined. For example, the controller 130 mayapply the driving signal to the driving unit 1101 every predeterminedperiod. In this case, the controller 130 may obtain the positioncorresponding to the first signal every predetermined period. Here, thepredetermined period may be a frame rate (FR) which is used for theimage generating device to obtain an image. In this case, the positioncorresponding to the first signal may be represented as first-first tofirst-n^(th) positions corresponding to n time points corresponding tothe predetermined period. Here, the n time points corresponding to thepredetermined period may be n time points that are evenly distributedwithin a predetermined period. However, the present invention is notlimited thereto, and a plurality of time points which are predeterminedwithin a predetermined period may be the n time points. Also, theposition corresponding to the second signal may be represented assecond-first to second-n^(th) positions corresponding to n time pointscorresponding to the predetermined period.

Also, when the driving signal is input to the driving unit 1101, thedriving unit 1101 may input the scanning driving signal to the scanningunit 1100, and the scanning unit 1100 may emit light to the object Oaccording to the scanning unit output signal when the scanning unit 1100is driven by the scanning unit driving signal. In this case, light thatis emitted to the object O according to the scanning unit output signaland that returns from the object O may be obtained through thelight-receiving unit 123 in the form of the light-receiving information.As shown in FIG. 52, the light-receiving information obtained by thelight-receiving unit 123 may be obtained by the controller 130 as theacquisition signal value. That is, as the light-receiving information issequentially obtained by the light-receiving unit 123 for apredetermined period, the controller 130 may obtain first to n^(th)acquisition values as the acquisition signal value. For convenience ofdescription, a format in which the position corresponding to the firstsignal, the position corresponding to the second signal, and theacquisition signal values are obtained by the controller 130 will beexpressed below as a dataset.

Therefore, the controller 130 may obtain position information of a pixelthat is determined according to a position corresponding to a firstsignal corresponding to an x-axis coordinate value of an image and aposition corresponding to a second signal corresponding to a y-axiscoordinate value of the image and may provide an image by usinginformation obtained by making the sequentially obtained acquisitionsignal values correspond to the position information of the plurality ofpixels, that is, by using the dataset.

7.1.1 Scheme in which Controller 130 Obtains Phase-Delayed Image orPhase-Calibrated Image

When the scanning module 110 scans the object O, the driving signal, thescanning unit driving signal, and the scanning unit output signal mayhave different phases. For convenience of description, the phases of thedriving signal, the scanning unit driving signal, and the scanning unitoutput signal being different will be expressed below as the phasesbeing delayed.

According to an embodiment, the phase being delayed may mean that theposition corresponding to the first signal or the position correspondingto the second signal at a predetermined time point within apredetermined period is different from a position at which the scanningunit output signal passes through the object O at the corresponding timepoint. In detail, the scanning unit 1100 may receive the scanning unitdriving signal and may emit light to the object O according to thescanning unit output signal, which is a signal output when the scanningunit 1100 is driven.

In this case, when position information corresponding to the scanningunit output signal can be obtained, the controller 130 may provide animage such that an acquisition signal value corresponds to the pixelposition of the image indicating a position corresponding to thescanning unit output signal. In this case, the image provided by thecontroller 130 may be an image with no phase delay.

However, when the image is provided from the controller 130, the firstsignal and the second signal of the driving signal may be used tospecify the pixel position information in the image. In this case, whenthe driving signal and the scanning unit output signal are delayed inphase and thus become different from each other, an image obtained bythe controller 130 using the position corresponding to the first signal,the position corresponding to the second signal, and the acquisitionsignal values may be a phase-delayed image.

Therefore, when the phase adjustment is performed such that the phase ofthe driving signal corresponds to the phase of the scanning unit outputsignal at a predetermined level or more, the controller 130 may obtainan image with no phase delay. Here, when the phase adjustment isperformed such that the phase of the driving signal and the phase of thescanning unit output signal match at a predetermined level or more, thephase of the driving signal may be adjusted using the input unit 140 ofthe controller 130. Also, when the phase adjustment is performed suchthat the phase of the driving signal and the phase of the scanning unitoutput signal correspond to each other at a predetermined level or more,the controller 130 may automatically adjust the phase of the drivingsignal using the algorithm. For convenience of description, the phaseadjustment being performed such that the phase of the driving signal andthe phase of the scanning unit output signal correspond to each other ata predetermined level or more will be expressed below as phasecalibration.

The table (a) of FIG. 53 shows a dataset of acquirable information whenthere is no phase delay. The table (b) of FIG. 53 shows a dataset ofacquirable information when there is some phase delay.

According to an embodiment, referring to the table (a) shown in FIG. 53,when the phase of the driving signal and the phase of the scanning unitoutput signal are not different, a plurality of acquisition signalvalues obtained at a pixel position specified through the positioncorresponding to the first signal and the position corresponding to thesecond signal may correspond to one another. For example, referring tothe table shown in FIG. 53, among the dataset values, a value X1obtained at the position corresponding to the first signal and a valueY1 obtained at the position corresponding to the second signal mayindicate one pixel position in an image which is expected to beobtained. Thus, an acquisition signal value I1 may be obtained at thepixel position represented by X1 and Y1.

Also, the position corresponding to the first signal and the positioncorresponding to the second signal may appear repeatedly within apredetermined period. Thus, the specified pixel position may appearrepeatedly through the position corresponding to the first signal andthe position corresponding to the second signal. Referring to the table(a) shown in FIG. 53, among the dataset values, X1 obtained at theposition corresponding to the first signal may be obtained at theposition corresponding to the first signal again after a predeterminedtime point. Also, Y1 obtained at the position corresponding to thesecond signal at the same time point as the time point when X1 isobtained may be obtained at the position corresponding to the secondsignal again after a predetermined time point. In this case, since thesame acquisition signal value I1 is obtained at the pixel positioncorresponding to X1 and Y1 at different time points, there may be nophase delay between the driving signal and the scanning unit outputsignal.

According to another embodiment, referring to the table (b) shown inFIG. 53, when the phase of the driving signal and the phase of thescanning unit output signal are different, a plurality of acquisitionsignal values obtained at a pixel position specified through theposition corresponding to the first signal and the positioncorresponding to the second signal may not correspond to one another.For example, referring to the table (b) shown in FIG. 53, among thedataset values, a value X3 obtained at the position corresponding to thefirst signal and a value Y1 obtained at the position corresponding tothe second signal may indicate one pixel position in an image which isexpected to be obtained. Accordingly, an acquisition signal value I1 maybe obtained at the pixel position represented by X3 and Y1.

Also, the position corresponding to the first signal and the positioncorresponding to the second signal may appear repeatedly within apredetermined period. Thus, the specified pixel position may appearrepeatedly through the position corresponding to the first signal andthe position corresponding to the second signal. Referring to the table(b) shown i FIG. 53, among the dataset values, X1 obtained at theposition corresponding to the first signal may be obtained at theposition corresponding to the first signal again after a predeterminedtime point. Also, Y1 obtained at the position corresponding to thesecond signal at the same time point as the time point when X1 isobtained may be obtained at the position corresponding to the secondsignal again after a predetermined time point. In this case, sincevalues I2 and I3 are obtained at the pixel position corresponding to X1and Y1 at different time points, there may be a phase delay between thedriving signal and the scanning unit output signal.

According to another embodiment, referring to FIGS. 52, 53A, and 53B, inorder to calibrate a phase delay between the driving signal and thescanning unit output signal, n position values obtained at the positioncorresponding to the first signal or the position corresponding to thesecond signal among the dataset may be obtained at another positionaccording to a delayed phase. For example, when there is a phase delayin the first signal of the driving signal, a value obtained at afirst-first position may be obtained at a first-n^(th) position, and avalue obtained at a first-n^(th) position may be obtained at afirst-(n−1)th position. In detail, referring to FIGS. 53A and 53B, whenthe phase of the first signal is delayed, the phase component of thefirst signal may be adjusted such that X1 obtained at a first-secondposition can be obtained at the first-first position. Thus, in thedataset obtained by the controller 130, the controller 130 may obtainthe position corresponding to the first signal as phase-adjusted values.Also, when there is a phase delay at the position corresponding to thesecond signal of the driving signal, a value obtained at a second-firstposition may be obtained at a second-n^(th) position, and a valueobtained at a second-n^(th) position may be obtained at a second-(n−1)thposition. In detail, referring to FIGS. 53A and 53B, when the phase ofthe second signal is delayed, the phase component of the second signalmay be adjusted such that Y1 obtained at a second-second position can beobtained at the second-first position. Thus, in the dataset obtained bythe controller 130, the controller 130 may obtain the positioncorresponding to the second signal as phase-adjusted values. However,the present invention is not limited thereto, and when there is a phasedelay between the positions corresponding to the first signal and thesecond signal of the driving signal, the values obtained at the positioncorresponding to the first signal and the position corresponding to thesecond signal may be obtained at another position according to a delayedphase.

According to another embodiment, in order to calibrate the phase delaybetween the driving signal and the scanning unit output signal, n valuesobtained in an acquisition signal value due to the light-receivinginformation may be obtained at the position of another obtained valueaccording to a delayed phase. For example, the value obtained at thefirst obtained value position may be obtained at the obtained valueposition, and the value obtained at the n^(th) obtained value positionmay be obtained at the (n−1)th obtained value position. In detail,referring to the tables (a) and (b) shown in FIG. 53, when there is nophase delay, the value I1 obtained at a pixel position specified throughX1 and Y1 may be obtained at the pixel position specified through X1 andY1 when there is a phase delay. That is, as shown in the table (b) ofFIG. 53, the controller 130 may adjust sequentially obtained acquisitionsignal values such that I1 obtained for the first obtained value can beobtained at the second obtained value.

Accordingly, the controller 130 may obtain a phase-calibrated imageusing the position corresponding to the first signal, the positioncorresponding to the second signal, or the acquisition signal value ofwhich a phase is calibrated.

An algorithm for obtaining a phase delay using a standard deviation ofan obtained image in order for the controller 130 to obtain the degreeto which a phase is delayed will be described below.

7.2 Acquisition of Phase Delay Value Using Standard Deviation

In order to obtain the degree to which a phase delay is present betweenthe driving signal and the scanning unit output signal, the acquisitionsignal value obtained by the controller 130 may be used. For example, inorder to obtain the degree to which the phase delay is present betweenthe driving signal and the scanning unit output signal, the controller130 may obtain a phase delay value using a difference between anacquisition signal value predicted to be obtained in the same pixel ofthe image obtained by the controller 130 and an acquisition signal valueincluding a standard deviation obtained at an actually predicted time.

Also, the controller 130 may obtain the phase delay degree using thedifference between the obtained signal value predicted to be obtained inthe same pixel and the acquisition signal value including the standarddeviation. It will be appreciated that the method of finding thedifference between the acquisition signal values is not limited thereto.In addition to finding the standard deviation between the acquisitionsignal values, the phase delay value may be obtained using an averageand a variance between the obtained signal values and the absolute valueof the difference between the acquisition signal values. However, forconvenience of description, the following description assumes that thestandard deviation is used to obtain a phase delay value.

7.2.1 Acquisition of Standard Deviation Using Prediction Time Point

FIG. 54 is a diagram showing a pixel 5400 having an acquisition signalvalue expected at a prediction time point when a phase is delayed(hereinafter referred to as an expected pixel corresponding to theprediction time point) and a pixel having an acquisition signal valueobtained at an actual prediction time point (hereinafter referred to asan actual pixel according to the prediction time point) along a path oflight emitted from the scanning module 110.

According to an embodiment, referring to FIG. 54, when a scanningpattern including a Lissajous pattern is formed according to the firstsignal or the second signal of the driving signal, the expected pixel5400 corresponding to the prediction time point may refer to a pixelwhen different time points are present along the light path but arerepresented as the same pixel position. In this case, a direction inwhich light is traveling at different time points when the light passesthrough the expected pixel 5400 corresponding to the prediction timepoint along the light path may include a first scanning direction and asecond scanning direction. A time point predicted when the light passesthrough the expected pixel 5400 corresponding to the prediction timepoint in the first scanning direction may be a first prediction timepoint, and a time point predicted when the light passes through theexpected pixel 5400 corresponding to the prediction time point in thesecond scanning direction may be a second prediction time point. Indetail, when the scanning unit output signal has a delayed phasecompared to the driving signal, a signal value 5410 obtained accordingto the first prediction time point and a signal value 5420 obtainedaccording to the second prediction time point may not be a signal valuecorresponding to the expected pixel 5400 corresponding to the predictiontime point.

FIG. 55 is a flowchart showing a process of performing phase calibrationusing a difference between signal values obtained at prediction timepoints. In detail, the phase calibration may include choosing a pixelpositioned where scanning directions intersect, obtaining a predictiontime point, obtaining an acquisition signal value 5410 corresponding toa first prediction time point, obtaining an acquisition signal value5420 corresponding to a second prediction time point, calculating adifference between the acquisition signal values corresponding to theprediction time points, and performing phase calibration.

Referring to FIG. 55, the choosing of a pixel positioned where scanningdirections intersect (S5100) may include choosing an expected pixelcorresponding to a prediction time point when a first scanning directionand a second scanning direction meet each other. In detail, there may bedifferent scanning directions with respect to a path of light passingthrough one pixel. Accordingly, in the case of a time point passingthrough the expected pixel 5400 corresponding to the prediction timepoint when the first scanning direction and the second scanningdirection meet each other in one scanning pattern, a time point passingthrough the expected pixel corresponding to the prediction time point inthe first scanning direction may be different from a time point passingthough the expected pixel corresponding to the prediction time point inthe second scanning direction. Therefore, when an intersection betweenthe first scanning direction and the second scanning direction along thelight path is selected, one pixel position may be represented atdifferent prediction time points of the driving signal. Accordingly,when the driving signal and the scanning unit output signal havedifferent phases, different obtained signal values corresponding to thescanning unit output signal may represent different values. Thus, anypixel corresponding to the first scanning direction and the secondscanning direction may be chosen from the driving signal.

Also, referring to FIG. 55, the obtaining of a prediction time point(S5110) may include obtaining, from a driving signal, a first time pointexpected to pass through the expected pixel corresponding to theprediction time point in the first scanning direction and a second timepoint expected to pass through the expected pixel corresponding to theprediction time point in the second scanning direction. In detail, sincea phase delay may occur between the driving signal and the scanning unitoutput signal, acquisition signal values obtained at the first timepoint and the second time point may differ when the light is emitted tothe object O according to the scanning unit output signal. Accordingly,after a prediction time point predicted to pass through the expectedpixel corresponding to the prediction time point according to thedriving signal is obtained, a standard deviation between acquisitionsignal values obtained according to the scanning unit output signal maybe found. Accordingly, the first time point or the second time point,which is a prediction time point predicted to pass through the expectedpixel corresponding to the prediction time point chosen from the drivingsignal, may be obtained.

Also, referring to FIG. 55, the obtaining of an acquisition signal valuecorresponding to a first prediction time point (S5120) and the obtainingof an acquisition signal value corresponding to a second prediction timepoint (S5130) may include obtaining acquisition signal valuescorresponding to the first prediction time point and the secondprediction time point corresponding to the scanning unit output signalwhen the controller 130 emits light to the object O according to thescanning unit output signal and obtains an acquisition signal valueusing returning light. In detail, since the phase of the driving signaland the phase of the scanning unit output signal may be different fromeach other, one signal value may need to be obtained from the expectedpixel corresponding to the prediction time point according to thedriving signal. However, the signal values corresponding to the firstprediction time point and the second prediction time point in thescanning unit output signal may be different from each other.Accordingly, a phase delay value may be obtained using an acquisitionsignal value corresponding to the first prediction time point acquirableaccording to the first prediction time point and an acquisition signalvalue corresponding to the second prediction time point acquirableaccording to the second prediction time point in the scanning unitoutput. However, FIG. 55 sequentially shows obtaining an acquisitionsignal value corresponding to the first prediction time point andobtaining an acquisition signal value corresponding to the secondprediction time point. However, the present invention is not limitedthereto, and the obtaining of the acquisition signal value correspondingto the second prediction time point may precede the obtaining of theacquisition signal value corresponding to the first prediction timepoint. Accordingly, a first time point or a second time point predictedas representing the expected pixel corresponding to the prediction timepoint may be present in the driving signal, and a signal value obtainedat the first time point or the second time point corresponding to thescanning unit output signal may be obtained.

Also, referring to FIG. 55, the calculating of the difference betweenthe acquisition signal values at the prediction time points (S5140) mayinclude calculating the standard deviation between the acquisitionsignal value corresponding to the first prediction time point and theacquisition signal value corresponding to the second prediction timepoint. In detail, when a phase delay occurs between the driving signaland the scanning unit output signal, a signal that would have beenobtained from the expected pixel corresponding to the prediction timepoint corresponding to the driving signal may be different from theacquisition signal value corresponding to the first prediction timepoint or the acquisition signal value corresponding to the secondprediction time point. However, when the acquisition signal valuecorresponding to the first prediction time point and the acquisitionsignal value corresponding to the second prediction time point matcheach other at a predetermined level or more, the acquisition signalvalue corresponding to the first prediction time point and theacquisition signal value corresponding to the second prediction time mayindicate the same pixel in the image obtained by the controller 130 ormay indicate pixels adjacent to the expected pixel corresponding to theprediction time point. Accordingly, when the acquisition signal valuecorresponding to the first prediction time point and the acquisitionsignal value corresponding to the second prediction time point match ata predetermined level or higher, the standard deviation between theobtained signal values may be small. Accordingly, when the standarddeviation is small, the phase delay value between the driving signal andthe scanning unit output signal may be small. Alternatively, when theacquisition signal value corresponding to the first prediction timepoint and the acquisition signal value corresponding to the secondprediction time point match are different from each other, theacquisition signal values may indicate pixels that are not adjacent tothe expected pixel corresponding to the prediction time point.Accordingly, when the acquisition signal value corresponding to thefirst prediction time point and the acquisition signal valuecorresponding to the second prediction time point are different, thestandard deviation between the obtained signal values may be large.Accordingly, when the standard deviation is large, the phase delay valuebetween the driving signal and the scanning unit output signal may belarge. However, the present invention is not limited thereto, and thephase delay value between the driving signal and the scanning unitoutput signal may not be large even when the standard deviation islarge. Accordingly, the expected pixel corresponding to the predictiontime point may not be one pixel, and one or more pixels may be chosen asthe expected pixels corresponding to the prediction time points. In thiscase, the degree to which the phase is delayed may be obtained using allstandard deviations between the acquisition signal values which areobtained through a phase-delayed signal in the expected pixelscorresponding to the prediction time points.

Also, referring to FIG. 55, the phase calibration (S5150) may includechanging a value obtained at the position corresponding to the firstsignal or the position corresponding to the second signal or changingthe position corresponding to the first signal, the positioncorresponding to the second signal, or the acquisition signal valueusing a phase value in which a value obtained by calculating thestandard deviation corresponding to the prediction time point whilechanging the acquisition signal value is less than or equal to apredetermined level. In detail, by changing the phase of the drivingsignal, the value obtained at the position corresponding to the firstsignal or the position corresponding to the second signal may bechanged. Thus, the expected pixel corresponding to the prediction timepoint may be chosen again, and the standard deviation value may becalculated. In this case, by changing the phase of the driving signal toa phase value with the smallest standard deviation, the positioncorresponding to the first signal or the position corresponding to thesecond signal may be changed, and the controller 130 may obtain aphase-calibrated image.

7.2.2 Acquisition of Standard Deviation Between Acquisition SignalValues Obtained in Same Pixel of Image Obtained by Controller 130

The controller 130 may obtain an acquisition signal value for the timepredetermined for a pixel of an image obtained by the controller 130.Accordingly, the controller 130 may find a standard deviation betweenacquisition signal values obtained at a pixel position for apredetermined time and may obtain an image obtained by changing thephase of the driving signal to a phase corresponding to when the valueof the standard deviation obtained by changing the phase of the drivingsignal is less than or equal to a predetermined level.

FIG. 56 is a flowchart showing a process of performing phase calibrationusing a standard deviation between acquisition signal values obtained ata pixel of an image obtained by the controller 130. In detail, the phasecalibration may include obtaining acquisition signal values of one pixelfor a predetermined time, calculating a difference between the obtainedacquisition signal values of the pixel, performing a calculation on apredetermined number of pixels, calculating a phase change value, andcalibrating a phase. For example, the obtaining of acquisition signalvalues of one pixel for a predetermined time may include obtaining lightintensity obtained at one pixel included in an image.

Referring to FIG. 56, the obtaining of acquisition signal values of onepixel for a predetermined time (S5200) may include obtaining anacquisition signal value acquirable from the light-receiving informationat the position of the pixel which can be obtained on the basis of theposition corresponding to the first signal and the positioncorresponding to the second signal. Here, the position corresponding tothe first signal may refer to an x-axis coordinate in pixel informationof the entire image obtained by the controller 130, and the positioncorresponding to the second signal may refer to a y-axis coordinate inpixel information of the entire image obtained by the controller 130.Accordingly, an x-axis coordinate and a y-axis coordinate determined inthe Cartesian coordinate system may represent one piece of positioninformation. Accordingly, one pixel position may be determined on thebasis of the position corresponding to the first signal and the positioncorresponding to the second signal. However, position information of apixel based on the positions corresponding to the first signal and thesecond signal of the driving signal may be obtained at least once for apredetermined time. In detail, when the position corresponding to thefirst signal and the position corresponding to the second signal arechosen, the position information of one pixel may be obtained. In thiscase, an acquisition signal value may be obtained for the positioninformation of one pixel. Also, since at least one acquisition signalvalue may be obtained for the position information of one pixel for apredetermined time, the controller 130 may obtain at least oneacquisition signal value for a predetermined time.

Here, the predetermined time may be the time taken for the positioncorresponding to the first signal to become the first-first positionagain and for the position corresponding to the second signal to becomethe second-first position again. However, the present invention is notlimited thereto, and the predetermined time may be the time taken forthe position corresponding to the first signal and the positioncorresponding to the second signal to be repeated several times and mayinclude any time.

Also, the obtained acquisition signal value may refer to the intensityof light returning from an object.

Also, referring to FIG. 56, the calculating of the difference betweenthe acquisition signal values of the obtained pixel (S5210) may includecalculating a difference between one or more acquisition signal valuesobtained by the controller 130. In detail, the controller 130 maycalculate the difference between the one or more acquisition signalvalues obtained at one pixel position based on the positioncorresponding to the first signal and the position corresponding to thesecond signal for a predetermined time. Here, the difference between theacquisition signal values may be a difference value including a standarddeviation, a variance, or the like. However, for convenience ofdescription, the following description assumes that the differencerefers to a standard deviation between the acquisition signal valuesobtained by the controller 130.

Also, referring to FIG. 56, the performing of calculation on apredetermined number of pixels (S5220) may include causing thecontroller 130 to calculate a standard deviation between acquisitionsignal values obtained at a predetermined number of pixel positions or aplurality of randomly determined pixel positions, in addition to thecalculating of the standard deviation between one or more acquisitionsignal values obtained at one pixel position. Here, a predeterminednumber or more of pixels which perform calculation may be one pixelposition of the image obtained by the controller 130. However, thepresent invention is not limited thereto, and the pixels may include allpixels of the image obtained by the controller 130. Also, thepredetermined number or more of pixels may include one or more pixelpositions.

According to an embodiment, the performing of calculation on apredetermined number of pixels (S5220) may include causing thecontroller 130 to obtain one piece of standard deviation informationusing the acquisition signal values calculated at the pixel positions aswell as calculating a standard deviation between the acquisition signalvalues obtained at each of the pixel positions. For example, standarddeviation information for all the pixels may be obtained using thestandard deviation calculated at one pixel position. In detail, thecontroller 130 obtaining one piece of standard deviation information mayfind the sum of the standard deviations obtained at each of the pixelpositions used for the calculation. However, the present invention isnot limited thereto, and the controller 130 may perform variouscalculations including an average, a product, a variance, and a standarddeviation of the standard deviations obtained at each of the pixelpositions. For convenience of description, the following descriptionassumes that the acquisition of one piece of standard deviationinformation refers to the calculation of the sum of the standarddeviations obtained at each of the pixel positions.

Also, referring to FIG. 56, the calculating of the phase change value(S5230) may include causing the controller 130 to change the positioncorresponding to the first signal, the position corresponding to thesecond signal, or the acquisition signal value and to obtain one pieceof standard deviation information. In detail, the position correspondingto the first signal or the position corresponding to the second signalwhich is obtained by changing the phase of the driving signal may bedifferent from position information of a pixel represented by theposition corresponding to the first signal or the position correspondingto the second signal before the phase of the driving signal is changed.Thus, since the order of the obtained signal values obtained by thecontroller 130 may not change, an acquisition signal value obtained forthe position information of the pixel represented by positionscorresponding to a first signal and a second signal included in adriving signal with a changed phase may be different from an acquisitionsignal value before the phase is changed. Accordingly, the standarddeviation of the acquisition signal value obtained at a pixel positionbased on the position corresponding to the first signal and the positioncorresponding to the second signal for a predetermined value may bedifferent from the standard deviation at the pixel position before thephase of the driving signal is changed. Accordingly, one piece ofstandard deviation information in a predetermined number of pixels mayvary depending on the change in phase of the driving signal. When thephase of the driving signal continues to be changed, one or more piecesof standard deviation information may be obtained.

According to an embodiment, when there is no phase delay between thedriving signal and the scanning unit output signal, the standarddeviation at the pixel position based on the position corresponding tothe first driving signal and the position corresponding to the seconddriving signal may have a value close to zero. In detail, the standarddeviation between acquisition signal values obtained in one pixel beingequal to zero may mean that there is no difference between the obtainedacquisition signal values. This may represent that the driving signaland the scanning unit output signal between which there is no phasedelay indicate the same position. Thus, when the standard deviationinformation using acquisition signal values obtained at a predeterminednumber of pixel positions is close to zero, this may mean that there islittle phase delay between the driving signal and the scanning unitoutput signal.

Accordingly, among the standard deviation information of phase-changeddriving signals, the phase of the driving signal exhibiting the smalleststandard deviation information may be determined as a phase to bechanged by the controller 130. However, the present invention is notlimited thereto, and the controller 130 may change the phase into thephase of a driving signal indicating standard deviation information at apredetermined level or less among standard deviation information of thephase-changed driving signals. However, for convenience of description,the following description assumes that the phase of a driving signalwith the smallest standard deviation information is to be changed by thecontroller 130.

Also, referring to FIG. 56, the phase calibration (S5240) may includechanging the phase of a driving signal into the phase of a drivingsignal exhibiting the smallest standard deviation information. Indetail, the phase calibration may be performed by changing a valueobtained at the position corresponding to the first signal or the secondsignal of the driving signal or by changing the acquisition signalvalue. Here, the phase of the driving signal with the smallest standarddeviation information may include the phases of the first signal and thesecond signal included in the driving signal. Accordingly, thecontroller 130 may change the position corresponding to the first signalaccording to the phase of the first signal with the smallest standarddeviation information and may change the position corresponding to thesecond signal according to the phase of the second signal with thesmallest standard deviation information. For convenience of description,the following description assumes that the changing according to thephase with the smallest standard deviation information refers to thephase calibration of the driving signal.

7.2.3 Search for Phase Calibration Value Using Trajectory TrackingMethod

FIG. 57 is a diagram showing standard deviation informationcorresponding to the change of the phase, wherein an x-axis indicates aphase corresponding to a first signal and a y-axis indicates a phasecorresponding to a second signal. In detail, in FIG. 57, a bright partmay indicate that the standard deviation information has a large value,and a dark part may indicate that the standard deviation information hasa small value. Accordingly, in order to calibrate the phases of thefirst signal and the second signal of the driving signal, the phasecorresponding to the first signal and the phase corresponding to thesecond signal may be obtained in the darkest part indicating that thestandard deviation information is smallest.

Also, FIG. 58 is a diagram showing standard deviation informationaccording to the change in phase and a path for changing the phasecorresponding to the first signal and the phase corresponding to thesecond signal, wherein an x-axis indicates the phase corresponding tothe first signal and a y-axis indicates the phase corresponding to thesecond signal. In detail, in FIG. 58, a bright part may indicate thatthe standard deviation information has a large value, and a dark partmay indicate that the standard deviation information has a small value.Accordingly, in order to calibrate the phases of the first signal andthe second signal of the driving signal, the phase corresponding to thefirst signal and the phase corresponding to the second signal may beobtained in the darkest part indicating that the standard deviationinformation is smallest.

According to an embodiment, referring to FIG. 58, the standard deviationinformation corresponding to the first signal and the second signal ofwhich phases are not calibrated may be standard deviation information ata position where a black star is present. Also, a white star mayindicate a value with the smallest standard deviation information. Inthis case, the controller 130 may change the phase of the first signaland the phase of the second signal in the black star into the phase ofthe first signal and the phase of the second signal in the white starwhile changing the phase corresponding to the first signal or the phasecorresponding to the second signal by a predetermined phase changeperiod. Here, the controller 130 may change the phase of the firstsignal and the phase of the second signal in the black star into thephase of the first signal and the phase of the second signal in thewhite star by a predetermined phase change period along a trajectory ofan arrow shown in FIG. 58. This may be expressed as the trajectorytracking method.

However, a trajectory for discovering the phase of the first signal andthe phase of the second signal having the smallest standard deviationinformation according to the trajectory tracking method is not limitedto the trajectory of the arrow shown in FIG. 58. The trajectory may bechanged by a predetermined phase change period in a direction of thephase corresponding to the second signal and then changed by apredetermined phase change period in a direction of the phasecorresponding to the first signal, or the phase of the first signal orthe second signal may be alternately changed by a predetermined phasechange period in the direction of the phase corresponding to the firstsignal and in the direction of the phase corresponding to the secondsignal.

In detail, the trajectory tracking method may be an algorithm fordiscovering the phases of the first signal and the second signal withthe smallest standard deviation information while changing the phase ofthe first signal or the phase of the second signal by a predeterminedphase change period. The algorithm for discovering the phases of thefirst signal and the second signal with the smallest standard deviationinformation according to the predetermined phase change period will bedescribed below.

7.2.4 Search for Phase Calibration Value Using Range Limiting Method

FIG. 59A is a diagram showing standard deviation information accordingto the change in phase of the first signal and the second signal andshowing that the phase variations of the first signal and the secondsignal are small, wherein an x-axis indicates the phase corresponding tothe first signal and a y-axis indicates the phase corresponding to thesecond signal. In detail, as shown in the image (a) of FIG. 59, a brightpart may indicate that the standard deviation information has a largevalue, and a dark part may indicate that the standard deviationinformation has a small value. Also, the image (b) of FIG. 59 is adiagram showing standard deviation information according to the changein phase of the first signal and the second signal and showing that thephase variation of the first signal or the second signal changes islarge, wherein an x-axis indicates the phase corresponding to the firstsignal and a y-axis indicates the phase corresponding to the secondsignal. In detail, as shown in the image (b) of FIG. 59, a bright partmay indicate that the standard deviation information has a large value,and a dark part may indicate that the standard deviation information hasa small value. Accordingly, in order to calibrate the phases of thefirst signal and the second signal of the driving signal, the phasecorresponding to the first signal and the phase corresponding to thesecond signal may be obtained in the darkest part indicating that thestandard deviation information is smallest.

For convenience of description, a process of setting a predeterminedrange at the phase of the first signal and the phase of the secondsignal according to the smallest standard deviation when the phasevariation of the first signal or the second signal is large, setting thephase variation of the first signal or the second signal to be smallwithin the corresponding range, and discovering the phase of the firstsignal and the phase of the second signal indicating the smalleststandard deviation information will be expressed below as a rangelimitation method.

According to an embodiment, referring to the image (a) of FIG. 59, whenthe phase variations of the first signal and the second signal aresmall, the amount of standard deviation information to be obtained bythe controller 130 may be large. When the amount of standard deviationinformation to be obtained by the controller 130 is large, thecontroller 130 may require more time to obtain the standard deviationinformation. Accordingly, in order for the controller 130 to spend lesstime in obtaining the standard deviation information, the phasevariation degrees of the first signal and the second signal may beincreased. In this case, according to the standard deviation informationobtained by the controller 130, the controller 130 may change the phasesof the first signal and the second signal. However, the phase of thefirst signal and the phase of the second signal according to thesmallest standard deviation information when the phase variations of thefirst signal and the second signal are large may be different from thephase of the first signal and the phase of the second signal accordingto the smallest standard deviation information when the phase variationsof the first signal and the second signal are small. In detail, when thephase variations of the first signal and the second signal are large,the controller 130 cannot obtain the standard deviation information forthe phase of the first signal and the phase of the second signalcorresponding to the smallest standard deviation information when thephase variations of the first signal and the second signal are small.Accordingly, when a predetermined range is set after the phasevariations of the first signal and the second signal are increased, thephase of the first signal and the phase of the second signal exhibitingthe smallest standard deviation information when the phase variations ofthe first signal and the second signal are small may not be included inthe corresponding range.

Accordingly, in order for the controller 130 to reduce the spent timeand obtain the phase of the first signal and the phase of the secondsignal exhibiting the smallest standard deviation information when thephase variations of the first signal and the second signal are small,the controller 130 may obtain the phase of the first signal and thephase of the second signal exhibiting the smallest standard deviationinformation using the trajectory tracking method and may obtain thephase of the first signal and the phase of the second signal exhibitingthe smallest standard deviation information in the range obtainedaccording to the trajectory tracking method by using the rangelimitation method.

8 Phase Calibration Using Predetermined Phase Change Period

In order for the controller 130 to obtain the phase of the first signaland the phase of the second signal with the smallest standard deviationinformation using the aforementioned trajectory tracking method, thecontroller 130 may discover the phase of the first signal and the phaseof the second signal with the smallest standard deviation informationusing a predetermined phase change period.

FIG. 60 is a diagram showing the phase of the first signal or the secondsignal with the smallest deviation information discovered using thetrajectory tracking method and a phase with the smallest standarddeviation information in the entire phase range of the first signal orthe second signal, wherein an x-axis indicates one of the phase of thefirst signal or the phase of the second signal, and a y-axis indicatesthe standard deviation information. In detail, in FIG. 60, a black starmay be the phase of the first signal or the second signal with thesmallest standard deviation information which is discovered using thetrajectory tracking method, and a white star may be a phase with thesmallest standard deviation information in the entire phase range of thefirst signal or the second signal.

According to an embodiment, in FIG. 60, the position of the black starand the position of the white star may be different. For example, aphase delay may be present between the driving signal and the scanningunit output signal when the scanning module 110 is driven (hereinafterreferred to as an initial delayed phase). In this case, the trajectorytracking method is used to discover the phase of the first signal or thesecond signal with the smallest standard deviation information at theinitial delayed phase according to a predetermined phase change period.Accordingly, when the discovery is performed by changing a phase by thepredetermined phase change period, the phase of the first signal or thesecond signal may be a phase represented by the position of the blackstar. However, when the difference between the phase represented by theposition of the black star and the phase represented by the position ofthe white star is not equal to the predetermined phase change period,the discovered phase with the smallest standard deviation informationmay be the phases of the first signal and the second signal representedby the position of the black star. Accordingly, no calibration may bemade with the phase for the controller 130 generating a high-resolutionimage having a calibrated phase which has been described with referenceto the image shown in (b) of FIG. 39, i.e., the phase represented by theposition of the white star when the standard deviation information issmallest in the entire phase range. For convenience of description, thefollowing description assumes that a phase corresponding to a localminimum is obtained when the controller 130 obtains a phase other than aphase corresponding to the smallest standard deviation information inthe entire phase range as a phase for calibrating the phase of thedriving signal.

According to another embodiment, after the phase is discovered using thetrajectory tracking method, the phase corresponding to the local minimummay be obtained using the range limitation method even when thecontroller 130 obtains a phase at which the information of the standarddeviation is minimized. In detail, the phase of the first signal or thephase of the second signal with the smallest standard deviationinformation may be obtained using the trajectory tracking method, andthe phase of the first signal or the phase of the second signal with thesmallest standard deviation information may be obtained using the rangelimitation method within a range predetermined from the phase of thefirst signal or the phase of the second signal obtained according to thetrajectory tracking method. However, when the range limitation method isused in a predetermined range, the phase of the first signal or thephase of the second signal with the smallest standard deviationinformation in the entire phase range may not be present in thepredetermined range on the basis of the phase of the first signal or thesecond signal obtained according to the trajectory tracking method.Accordingly, even when the phase of the first signal or the secondsignal with the smallest standard deviation information is discoveredusing the range limitation method after the discovery is made accordingto the trajectory tracking method, the phase corresponding to the localminimum may be obtained.

A predetermined phase change period in the trajectory tracking methodand a predetermined change range in the range limitation method fordiscovering the phase of the first signal or the second signal with thesmallest standard deviation information in the entire phase range willbe described below.

8.1 Predetermined Phase Change Period Acquisition Method

As described above with reference to FIG. 57, a bright part and a darkpart indicating the degree of the standard deviation information(hereinafter referred to as light and shade) may be repeated in acertain pattern. Accordingly, in order to obtain the phase of the firstsignal or the second signal with the smallest standard deviationinformation in the entire phase range using the trajectory trackingmethod, a period in which light and shade is repeated in a certainpattern may be necessary.

FIG. 61 is a diagram showing a fill factor (FF) of an image obtained bythe controller 130 along with the change in phase, wherein an x-axisindicates a phase corresponding to a first signal and a y-axis indicatesa phase corresponding to a second signal. Here, the FF may indicate theratio of pixels based on the position corresponding to the first signaland the position corresponding to the second signal to all pixels of animage to be generated by the controller 130 when the scanning module 110emits light toward the object O. However, the present invention is notlimited thereto, and the FF may indicate the ratio of the area occupiedby a path in which light has passed according to the scanning pattern tothe area where the scanning is performed when the scanning module 110 isscanning the object O. In detail, in FIG. 61, a bright part may indicatea part having a high FF, and a dark part may indicate a part having alow FF. For convenience of description, the bright part and the darkpart will be expressed as light and shade.

According to an embodiment, the light-and-shade pattern of FIG. 57 andthe light-and-shade pattern of FIG. 61 may be the same. In detail, aperiod in which the bright part indicated by the black arrow is repeatedin FIG. 57 may be the same as a period in which the bright partindicated by the black arrow is repeated. Accordingly, the period inwhich light and shade is repeated in a certain pattern in FIG. 57 may becalculated using the period of a pattern in which light and shade isrepeated in FIG. 61.

According to an embodiment, in order to calculate a pattern in which anFF is repeated according to FIG. 61, information of the driving signalgenerated by the controller 130 may be necessary. Here, the controller130 may use an alternating current signal as the driving signal.Accordingly, since the waveform of the alternating current signal isrepeated in a certain period, the controller 130 may obtain a pattern inwhich light and shade is repeated in one axis direction in FIG. 61 bycalculating a period in which an alternating current signal of the firstsignal or the second signal of the driving signal is repeated.

$\begin{matrix}{y = {A\; {\sin \left( {2\pi {f_{y}\left( {t + \frac{\varphi_{y}}{2\pi f_{y}}} \right)}} \right)}}} & \left\lbrack {{Formula}\mspace{14mu} 5} \right\rbrack\end{matrix}$

The waveform of the alternating current signal in which the secondsignal of the driving signal is generated may be expressed as Formula 5above. Here, Y may indicate the position corresponding to the secondsignal, and A may indicate the amplitude of the second signal. Also,f_(y) may be the frequency component of the second signal, and ϕ_(y) maybe the phase component of the second signal. Also, like the secondsignal, the first signal may also be expressed using Formula 5 above,and the frequency component and the phase component for expressing theposition of the first signal may be expressed as the frequency componentand the phase component corresponding to the x-axis direction.

Here, when the phase component of the first signal ϕ_(x) is determined,the same position may be repeated for the second signal according to thephase component of the second signal. For example, when the phasecomponent of the first signal is zero, the phase component of the secondsignal ϕ_(y) may be repeated every

$\frac{\pi}{n_{x}}.$

Here, n_(x) may be a component obtained by dividing the frequencycomponent of the first signal by the greatest common divisor(hereinafter, referred to as GCD) obtained using the frequency componentof the first signal and the frequency component of the second signal.Likewise, n_(y) may be a component obtained by dividing the frequencycomponent of the second signal by the GCD, and n_(x) and n_(y) may becomprise integers which have no divisors except one.

In the case of the second signal, the position corresponding to thesecond signal may be repeated whenever ϕ_(y) is

$\frac{\pi}{n_{x}},$

and thus the position corresponding to the second signal may repeatedlyappear whenever

$\frac{\varphi_{y}}{2\pi \; f_{y}}\mspace{14mu} {is}\mspace{14mu} {\frac{1}{2n_{x}n_{y}}.}$

Even in the case of the first signal, the position corresponding to thefirst signal may appear repeatedly whenever ϕ_(x) is

$\frac{\pi}{n_{y}},$

and thus the first signal may appear repeatedly whenever

$\frac{\varphi_{x}}{2\pi \; f_{x}}\mspace{14mu} {is}\mspace{14mu} {\frac{1}{2n_{x}n_{y}}.}$

In this case, the position corresponding to the second signal may berepeated according to

$\frac{1}{2n_{x}n_{y}}$

only when the GCD is 1. Thus, when the GCD is not 1, the phase may berepeated by

$\frac{1}{2n_{x}n_{y}{GCD}}$

in order to repeat the position corresponding to the first signal or thesecond signal. Here,

${\frac{1}{2n_{x}n_{y}{GCD}}\mspace{14mu} {is}\mspace{14mu} \frac{GCD}{2f_{x}f_{y}}},$

and thus the position of the first signal or the second signal mayappear repeatedly when a period in which the phase component of thefirst signal or the second signal changes is

$\frac{GCD}{2f_{x}f_{y}}.$

Therefore, when the predetermined phase change period is

$\frac{GCD}{2f_{x}f_{y}},$

the FF corresponding to FIG. 61 may appear repeatedly. However, thepresent invention is not limited thereto, and the FF may appearrepeatedly even when the predetermined phase change period is an integermultiple of

$\frac{GCD}{2f_{x}f_{y}}.$

8.1.1 Discovery of Phase Calibration Value Using Predetermined PhaseChange Period

A phase may be calibrated by obtaining the phase of the first signal orthe second signal with the smallest standard deviation information usingthe above-described predetermined phase change period. In detail, thetrajectory tracking method may be used on the basis of the predeterminedphase change period. Also, even when the range limitation method is usedon the basis of the phase obtained by the controller 130 using thetrajectory tracking method, the predetermined phase change period may beused.

8.1.1.1 Trajectory Tracking Method Using Predetermined Phase ChangePeriod

FIG. 62 is a flowchart showing a process of discovering the phase of thefirst signal or the second signal having the smallest standard deviationinformation when the trajectory tracking method is performed based onthe predetermined phase change period. In detail, like theabove-described trajectory tracking method, the phase of the firstsignal or the second signal having the smallest standard deviationinformation may be discovered in the phase direction for the firstsignal or the second signal on the basis of the predetermined phasechange period.

Referring to FIG. 62, the setting of the initial position (S5300) mayinclude setting the phase of the first signal or the second signal at aninitial stage when the phase of the first signal or the second signalwith the smallest standard deviation information is discovered using thetrajectory tracking method. In detail, the controller 130 may obtain theposition corresponding to the first signal or the position correspondingto the second signal by changing the phase component of the first signalor the second signal to a phase perpendicular to the phase component ofthe first signal or the second signal of the driving signal which isinput to drive the driving unit 1101. Here, an angle at which phasecomponents are perpendicular to each other may refer to 90 degrees or anangle close to 90 degrees which may be regarded as an angle at which thephase components are substantially perpendicular to each other. However,the initial phase may be set to have a phase difference substantiallyclose to 45 degrees depending on a direction in which the phase isdiscovered. However, the present invention is not limited thereto, andthe initial phase may be set in the entire phase range. For example,when a signal having a resonant frequency is input to an object, thephase of a signal output according to the signal input to the object maybe delayed by 90 degrees from the phase of the signal having theresonant frequency. Accordingly, when the first signal or the secondsignal having the resonant frequency of the scanning unit 1100 is inputto the scanning unit 1100, the phase of the output signal of thescanning unit may be changed to an angle close to 90 degrees compared tothe first signal or the second signal of the driving signal input fromthe controller 130. Accordingly, the initial phase of the first signalor the second signal at which the discovery is started may be set to 90degrees or an angle close to 90 degrees. Thus, when the initial positionfor the discovery is set to 90 degrees or an angle close to 90 degrees,the controller 130 can reduce the time required for the trajectorytracking method to discover a phase delay between the driving signal andthe scanning unit output signal.

Also, referring to FIG. 62, the shift in the first direction (S5310) mayinclude obtaining standard deviation information having the phase of thefirst signal or the second signal changed by the controller 130according to the predetermined phase change period in the phasedirection corresponding to the first signal or the phase directioncorresponding to the second signal. Here, referring back to FIG. 58, thefirst direction may be an x-axis indicating the phase of the firstsignal or an y-axis indicating the phase of the second signal. Likewise,the second direction may be an x-axis indicating the phase of the firstsignal or a y-axis indicating the phase of the second signal. Forconvenience of description, the following description assumes that thefirst direction is an x-axis direction indicating the phase of the firstsignal and the second direction is a y-axis direction indicating thephase of the second signal. Also, the controller 130 may change thephase of the driving signal in the first direction or in the seconddirection by a predetermined phase change period, and the change may beexpressed as a shift. For example, a phase before the controller 130changes the phase of the driving signal in the first direction by thepredetermined phase change period may be expressed as a pre-shift phase,and a phase after the controller 130 changes the phase of the drivingsignal by the predetermined phase change period may be expressed as apost-shift phase. Accordingly, the controller 130 may obtain standarddeviation information using the phase after the shift in the firstdirection. In this case, the phase may not change in the seconddirection but may be changed to the post-shift phase in the firstdirection.

Also, referring to FIG. 62, the comparing of pre-shift standarddeviation information to post-shift standard deviation information(S5320) includes causing the controller 130 to compare standarddeviation information corresponding to the pre-shift phase to standarddeviation information corresponding to the post-shift phase during theshift in the first direction. For example, when the standard deviationinformation corresponding to the phase before the shift in the firstdirection is larger than the standard deviation informationcorresponding to the phase after the shift in the first direction, thecontroller 130 may obtain the phase after the shift in the firstdirection as the current phase and then may change the current phase inthe first direction by the predetermined phase change period. Also, whenthe standard deviation information corresponding to the phase before theshift in the first direction is smaller than the standard deviationinformation corresponding to the phase after the shift in the firstdirection, the controller 130 may obtain the phase before the shift inthe first direction as the current phase and then may change the currentphase in the second direction by the predetermined phase change period.

Also, referring to FIG. 62, the shift in the second direction (S5330)may include causing the controller 130 to obtain a phase with thesmallest standard deviation information in the first direction and shiftthe phase in the second signal. In detail, when the controller 130performs comparison on the standard deviation information correspondingto the phase shift in the first direction and obtains the phase of thefirst signal with the minimal standard deviation information, the phaseof the second direction may be changed in the second direction by thepredetermined phase change period such that the standard deviationinformation corresponding to the phase of the second signal in thesecond direction is minimal. Accordingly, the phase in the firstdirection may not be changed, and only the phase in the second directionmay be changed by the predetermined phase change period. The controller130 may obtain the standard deviation information using the phase afterthe shift in the second direction.

Also, referring to FIG. 62, the comparing of pre-shift standarddeviation information to post-shift standard deviation information(S5340) includes causing the controller 130 to compare standarddeviation information corresponding to the pre-shift phase to standarddeviation information corresponding to the post-shift phase during theshift in the second direction. For example, when the standard deviationinformation corresponding to the phase before the shift in the seconddirection is larger than the standard deviation informationcorresponding to the phase after the shift in the second direction, thecontroller 130 may obtain the phase after the shift in the seconddirection as the current phase and then may change the current phase inthe second direction by the predetermined phase change period. Also,when the standard deviation information corresponding to the phasebefore the shift in the second direction is smaller than the standarddeviation information corresponding to the phase after the shift in thesecond direction, the controller 130 may obtain the phase before theshift in the second direction as the current phase.

Also, referring to FIG. 62, the determining of the phase calibrationvalue (S5350) may include calibrating the phase of the driving signalusing the phase of the first signal obtained by the controller 130through the shift in the first direction and calibrating the phase ofthe driving signal using the phase of the second signal obtained by thecontroller 130 through the shift in the second direction. In detail, thestandard deviation information corresponding to the phase of the firstsignal after the final shift in the first direction and the phase of thesecond signal after the final shift in the second direction may indicatea value with the smallest standard deviation information in the entirephase range. Accordingly, the phase of the first signal and the phase ofthe second signal which are obtained by the controller 130 may indicatethe degree to which the phase of the scanning unit output signal isdelayed from the phase of the driving signal. Accordingly, the phase ofthe driving signal may be calibrated using the phase of the first signaland the phase of the second signal which are obtained by the controller130, and the controller 130 may obtain or provide an image using theacquisition signal values and the positions corresponding to the firstsignal and the second signal of the driving signal.

According to an embodiment, the method of discovering the phase with thesmallest standard deviation information as shown in FIG. 62 may be equalto the discovery direction shown in FIG. 58. In FIG. 62, when adirection in which the phase of the driving signal is moved for thefirst time, i.e., the first direction, is a y-axis, the controller 130may discover a phase according to a movement path from the black star,which is an initial setting phase, to the white star in order todiscover a value with the smallest standard deviation, as shown in FIG.58.

FIGS. 63 and 64 are diagrams showing a path for discovering the phase ofthe first signal or the second signal with the smallest standarddeviation information using the trajectory tracking method. In FIGS. 63and 64, an x-axis may indicate the phase corresponding to the firstsignal, and a y-axis may indicate the phase corresponding to the secondsignal.

According to an embodiment, a path for the controller 130 to discoverthe phase of the first signal or the second signal with the smalleststandard deviation information using the predetermined phase changeperiod is not limited to the path shown in FIG. 58 and may be the pathshown in FIG. 63. For example, when the initial phase at which thediscovery is started is the same as at least one of the phases of thefirst signal and the second signal having the smallest standarddeviation information, the controller 130 may discover a phase with thesmallest standard deviation information in only one direction.

According to another embodiment, a path for the controller 130 todiscover the phase of the first signal or the second signal with thesmallest standard deviation information using the predetermined phasechange period is not limited to that shown in FIG. 58 and may be thepath shown in FIG. 64. In detail, as shown in FIG. 58, the phase of thedriving signal with the smallest standard deviation information may bediscovered in one direction first, and then the phase of the drivingsignal with the smallest standard deviation information may bediscovered in another direction. However, as shown in FIG. 64, thediscovery is performed in one direction, in another direction at thephase in which the standard deviation information is not smallest, andthen in the one direction again. However, the present invention is notlimited thereto, and the controller 130 may perform the discoveryalternately in the first direction and in the second direction. When avalue with the smallest standard deviation information is discovered inone direction, the shift direction may no longer be changed.

According to another embodiment, the controller 130 may discover thephase of the first signal or the second signal with the smalleststandard deviation in a diagonal direction between the first directionand the second direction. In detail, as shown in FIG. 57, since lightand shade, which indicates the degree of the standard deviationinformation, is repeated in a certain pattern, the standard deviationinformation is repeated in the first direction or in the seconddirection. Furthermore, light and shade, which indicates standarddeviation information, is repeated in a certain pattern in a diagonaldirection between the first direction and the second direction.Accordingly, the controller 130 may discover a phase with the smalleststandard deviation information in the diagonal direction between thefirst direction and the second direction. In this case, when thediscovery is performed in the diagonal direction between the firstdirection and the second direction, the discovery may be performed inthe diagonal direction between the first direction and the seconddirection by changing the phase by the half of the aforementionedpredetermined phase change period. However, the present invention is notlimited thereto. When the discovery is performed in a direction in whichboth of the phase in the first direction and the phase in the seconddirection are increased or decreased, the discovery may be performedwith any phase change value regardless of the predetermined phase changeperiod. In this case, the controller 130 may obtain a phase with theminimum standard deviation information according to the discovery in thediagonal direction. Also, the controller 130 may additionally discoverthe phase of the driving signal with the smallest standard deviationinformation in the first direction or in the second direction at thephase with the smallest standard deviation information discovered in thediagonal direction.

8.1.1.2 Phase Discovery Using Range Limitation Method after TrajectoryTracking Method

When the controller 130 obtains the phase of the driving signal with thesmallest standard deviation information by the trajectory trackingmethod, the obtained phase of the driving signal may be the phasecorresponding to the local minimum. Accordingly, the controller 130 mayobtain the phase with the smallest standard deviation information in theentire phase range by using a predetermined phase variation for thephase of the driving signal discovered by the trajectory trackingmethod.

FIG. 65 is a flowchart showing a process of obtaining a phasecorresponding to the trajectory tracking method through a predeterminedphase change period, discovering a phase with the smallest standarddeviation information in the entire phase range using the rangelimitation method, and calibrating the phase of the first signal or thesecond signal to the corresponding phase in order for the controller 130to perform phase calibration.

Referring to FIG. 65, the setting of a range for discovering the phasewith the smallest standard deviation information may include causing thecontroller 130 to set the phase obtained by the controller 130 using thetrajectory tracking method as the center of the set range and to obtainthe phase having the smallest standard deviation information in theentire phase range. In detail, since the discovery is performed whilethe phase of the driving signal is changed by the predetermined phasechange period through the trajectory tracking method, the phase with thesmallest standard deviation information in the entire phase range may bepositioned at a distance less than the predetermined phase change periodfrom the phase obtained by the controller 130 using the trajectorytracking method. Accordingly, the phase obtained by the controller 130through the trajectory tracking method may be set as a center point, therange of the phase corresponding to the first signal may be set to bethe predetermined phase change period from the center point, and therange of the phase corresponding to the second signal may also be set tobe the predetermined phase change period from the center point.Accordingly, the controller 130 may obtain the phase with the smalleststandard deviation information in the entire phase range by using therange limitation method within a certain range that is set from thecenter point.

However, the present invention is not limited thereto, and thecontroller 130 may set an arbitrary range on the basis of the phaseobtained by the controller 130 using the trajectory tracking method.Here, a phase which is a reference for setting the range may be thecenter point within the set range and may be positioned within theboundary of the set range. Also, the arbitrary range may be set usingthe predetermined phase change period or may be set using an arbitraryphase interval instead of the predetermined phase change period.However, in order to reduce the time required for the controller 130 todiscover the phase with the smallest standard deviation information, thearbitrary range set for the range limiting method may be a phaseinterval smaller than the predetermined phase change period.

Also, referring to FIG. 65, the calibrating of the phase of the firstsignal (S5410) and the calibrating of the phase of the second signal(S5420) may include calibrating the phase of the first signal or thesecond signal on the basis of the phase obtained by the controller 130when the range for discovering the phase with the smallest standarddeviation information is set. In detail, the phase obtained by thecontroller 130 when the range for discovering the phase with thesmallest standard deviation information is set may be a delayed phasebetween the phase of the driving signal and the phase of the scanningunit output signal. Accordingly, the phase of the first signal and thesecond signal of the driving signal may be calibrated with the delayedphase.

8.1.1.3 Phase Discovery Using Predetermined Unit after TrajectoryTracking Method

As described above, when the controller 130 obtains the phase of thedriving signal with the smallest standard deviation information by usingthe trajectory tracking method, the obtained phase of the driving signalmay be the phase corresponding to the local minimum. Accordingly, thecontroller 130 may obtain the phase with the smallest standard deviationinformation in the entire phase range using a unit smaller than thepredetermined phase change period on the basis of the phase of thedriving signal discovered by the trajectory tracking method.

In detail, when the delayed phase of the driving signal is discoveredusing the trajectory tracking method by the predetermined phase changeperiod, the obtained phase may be the phase corresponding to the localminimum of the standard deviation information. The local minimum may beobtained when the phase with the smallest standard deviation informationin the entire phase range is present in a range smaller than thepredetermined phase change period from the phase discovered using thetrajectory tracking method.

Accordingly, in order for the controller 130 to obtain the phase withthe smallest standard deviation information in the entire phase range, apredetermined unit, which is a unit smaller than the predetermined phasechange period, may be used.

FIG. 66 is a flowchart showing a process of discovering a phase usingthe trajectory tracking method and then obtaining the phase with theminimal standard deviation information in the entire phase range using aunit smaller than the phase change period used in the trajectorytracking method.

Referring to FIG. 66, the discovering of a phase using the trajectorytracking method (S5800) may include discovering the phase with thesmallest standard deviation information corresponding to the trajectorytracking method by using the aforementioned predetermined phase changeperiod. In detail, the phase may be discovered in the first directionand the second direction by the predetermined phase change period, andthe phase discovery may be performed in a diagonal direction between thefirst direction and the second direction, rather than in the firstdirection and the second direction. For convenience of description, thefollowing description assumes that when the phase is discovered usingthe trajectory tracking method, the phase discovery is performed in thefirst direction and the second direction.

Referring to FIG. 66, the calibrating of the phase of the first signalusing the predetermined unit (S5810) and the calibrating of the phase ofthe second signal using the predetermined unit (S5820) may includediscovering the phase with the minimal standard deviation informationusing the predetermined unit and calibrating the phase of the firstsignal and the phase of the second signal using the corresponding phase.Here, the predetermined unit may be a phase change value having asmaller value than the predetermined phase change period. In detail, thephase obtained by the controller 130 when the phase discovery isperformed using the trajectory tracking method (S5800) may be a localminimum, not the phase with the minimal standard deviation informationin the entire phase range. Accordingly, by decreasing a phase variationin the phase obtained using the trajectory tracking method, the phasewith the minimal standard deviation information in the entire phaserange may be discovered.

In detail, when the discovery has been performed in any one of the firstdirection and the second direction in order to obtain the phase in thetrajectory tracking method, the discovery may be re-performed using thepredetermined unit in the other direction, which is different from theone of the first direction and the second direction, i.e., the finaldirection in which the discovery has been performed to obtain the phase.For example, when the direction in which the discovery has been finallyperformed to obtain the phase in the trajectory tracking method is thefirst direction, the discovery may be performed in the second directionusing a predetermined unit in which a phase variation is reduced.

In this case, when the phase with the smallest standard deviationinformation is discovered in the corresponding direction after thediscovery is performed using the predetermined unit in a directiondifferent from the final discovery direction of the trajectory trackingmethod, the phase with the standard deviation information may bediscovered in a direction different from the direction in which thediscovery is performed using the predetermined unit for the first time.For example, when the direction in which the discovery is performedusing the predetermined unit for the first time is the second direction,the phase with the minimal standard deviation information may bediscovered in the first direction on the basis of the phase of thesecond signal corresponding to the second direction with the minimalstandard deviation information.

When the controller 130 discovers and obtains, using the predeterminedunit, the phase of the first signal corresponding to the first directionand the phase of the second signal corresponding to the second directionwith the minimal standard deviation information in the entire phaserange, the phases of the first signal and the second signal of thedriving signal may be calibrated with the obtained phase.

8.2 Increase in FF Through Change of Driving Signal Input to DrivingUnit 1101

In order for the quality of an image obtained by the controller 130 tobe determined as good, there may need to be no phase delay between thedriving signal and the scanning unit output signal, or the controller130 may need to calibrate the phase of the driving signal by the delayedphase when the image is obtained. In this case, the quality of the imagemay be expressed as “good.” Also, as another cause, when the scanningmodule 110 emits light to the object O, the ratio of the area occupiedby the scanning pattern to the area to which the light is emitted or theratio of a pixel position where an acquisition signal value is presentin an image obtained by the controller 130 to all pixels of the obtainedimage may be high. In this case, the quality of the image may beexpressed as “good.” Here, the ratio of the area occupied by thescanning pattern to the area to which the light is emitted or the ratioof a pixel position where an acquisition signal value is present to allthe pixels of the image obtained by the controller 130 may be expressedas an FF. Also, the scanning pattern in the area to which the light isemitted may include a Lissajous pattern.

According to an embodiment, the phase delay between the driving signaland the scanning unit output signal may not be large or may be reducedby calibrating the phase of the driving signal. In this case, as theratio of the area occupied by the scanning pattern to the area to whichlight is emitted increases, the ratio of the pixel position where theacquisition signal value is present to all the pixels of the imageobtained by the controller 130 may increase. However, the presentinvention is not limited thereto. Even when the phase delay between thedriving signal and the scanning unit output signal is small or thedifference between the calibrated phase of the driving signal and thephase of the scanning unit output signal is great, the FF may be high.

A method of increasing the FF of the image obtained by the controller130 by changing the phase of the driving signal will be described below.

8.2.1 Relationship Between FF and Predetermined Phase Change Period

FIGS. 67 and 68 are diagrams showing the change in FF value due to thedifference in phase between the first signal and the second signal,wherein an x-axis indicates a time unit indicating the phases of thefirst signal and the second signal among signals for generating thescanning pattern, including the driving signal, the scanning unitdriving signal, and the scanning unit output signal, and a y-axisindicates FF in units of %.

In detail, FIG. 67 is a diagram showing the change in FF due to thedifference between the phase of the first signal and the phase of thesecond signal when values obtained by dividing the frequency componentof the first signal and the frequency component of the second signal bythe greatest common divisor of the frequency components of the firstsignal and the second signal (hereinafter referred to as a unitfrequency of the first signal and a unit frequency of the second signal)are all odd numbers.

Also, FIG. 68 is a diagram showing the change in FF due to thedifference between the phase of the first signal and the phase of thesecond signal when only one of the unit frequency of the first signaland the unit frequency of the second signal is an even number.

According to an embodiment, the FF may be repeated depending on thedifference between the phase of the first signal and the phase of thesecond signal.

The intervals indicated by the black arrows shown in FIGS. 67 and 68indicate predetermined phase change periods. In detail, a period inwhich a value for maximizing the FF due to the difference between thephase of the first signal and the phase of the second signal is repeatedis as follows.

|φ_(x)−φ_(y)|=½Dip+N*Dip=A  [Formula 6]

|φ_(x)−φ_(y)|=0+N*Dip=A  [Formula 7]

Here, Formula 6 above indicates a period in which the difference betweenthe phase of the first signal and the phase of the second signal wherethe FF is maximized (hereinafter referred to as the phase difference) isrepeated when the unit frequency of the first signal and the unitfrequency of the second signal are all odd numbers. In detail, Dip mayindicate a predetermined phase change period, and N may indicate aninteger including a natural number. Also, A may indicate a period inwhich a phase difference for maximizing the FF of the image obtained bythe controller 130 is repeated.

Also, Formula 7 indicates a period in which a phase difference formaximizing the FF is repeated when only one of the unit frequency of thefirst signal and the unit frequency of the second signal is an evennumber. In detail, Dip may indicate a predetermined phase change period,and N may indicate an integer including a natural number. Also, A mayindicate a period in which a phase difference for maximizing the FF ofthe image obtained by the controller 130 is repeated.

FIG. 69 is a flowchart showing a process of adjusting the phase of thedriving signal and increasing the FF of the image obtained by thecontroller 130.

Referring to FIG. 69, the obtaining of period A (S5500) may includecausing the controller 130 to obtain the period of the phase differencein which a high FF is repeated on the basis of the frequency componentof the driving signal. In detail, in Formula 6 or Formula 7, Dip mayindicate a predetermined phase change period and thus may be obtained bythe frequency component of the first signal and the frequency componentof the second signal. Here, when the driving signal is input to thedriving unit 1101, the frequency components of the first signal and thesecond signal may not change. Thus, a period A in which a phasedifference for maximizing the FF of the image obtained by the controller130 is repeated may be set when the driving signal is input to thedriving unit 1101, and period A may be obtained by the controller 130.

Also, referring to FIG. 69, the obtaining of the phase calibration value(S5510) includes causing the controller 130 to obtain a delayed phasevalue between the phase of the driving signal and the phase of thescanning unit output signal. In detail, when the controller 130 obtainsthe delayed phase value, the aforementioned standard deviation or thepredetermined phase change period may be used. However, the presentinvention is not limited thereto, and even when the delayed phase valuebetween the phase of the driving signal and the phase of the scanningunit output signal is obtained by a method other than theabove-described method, the controller 130 may obtain the delayed phasevalue.

Also, referring to FIG. 69, the changing of the phase of the drivingsignal (S5520) may include changing the phase of the driving signalusing the phase of at least one of the obtained period A, a valueobtained by delaying the phase of the first signal, a value obtained bydelaying the phase of the second signal, and the driving signal. Forconvenience of description, the following description assumes that thephase of the second signal is changed. In detail, when a phase delay ispresent between the phase of the driving signal and the phase of thescanning unit output signal, the scanning unit output signal may beobtained by adding the delayed phase to the phase of the driving signal.Also, since the period for maximizing the value of the FF in thescanning unit output signal is also A, the difference between the phasesof the first signal and the second signal of the scanning unit outputsignal may be a. Accordingly, the phase of the second signal of thescanning unit output signal and the phase of the first signal of thescanning unit output signal may have a difference of a. Here, the phaseof the first signal of the scanning unit output signal may be a valueobtained by adding the degree to which the phase of the first signal isdelayed to the phase of the first signal of the driving signal, and thephase of the second signal of the scanning unit output signal may be avalue obtained by adding the degree to which the phase of the secondsignal is delayed to the phase of the second signal of the drivingsignal. Accordingly, the following formula may be obtained.

φ_(y)=φ_(x)+φ_(cx)−φ_(cy) ∓A  [Formula 8]

Referring to Formula 8 above, the phase of the second signal of thedriving signal to be changed, i.e., φ_(y) may have a phase difference ofa from the phase of the first signal of the scanning unit output signal,which is a value obtained by adding the delayed phase of the firstsignal of the driving signal to the phase of the first signal of thedriving signal, minus the delayed phase of the second signal of thedriving signal. Accordingly, when the phase of the first signal of thedriving signal is not changed and the phase of the second signal of thedriving signal is changed according to Formula 4, the controller 130 mayobtain an image having a high FF.

9 Acquisition of Image with FF Increased Using Plurality of DrivingSignals

In the case of a device for emitting light to an object O using ascanning pattern including a Lissajous pattern, a spiral pattern, and araster pattern and for obtaining and generating an image, the ratio ofthe area occupied by the scanning pattern to the area to which the lightis emitted or the ratio of the pixel position where an acquisitionsignal value is present to all pixels of an image obtained by thecontroller 130, i.e., an FF, is not 100%, and thus the quality orresolution of the image may be low.

FIG. 70 is a diagram showing that a path of emitted light varies when aphase is changed.

Also, referring to FIG. 70, a path in which light is emitted may varywhen the phase component of the driving signal for generating aLissajous pattern is changed. Accordingly, when at least one of thephases of the first signal and the second signal of the driving signalis changed, a scanning pattern having a high FF as shown in the image(b) or (c) of FIG. 70 may be provided instead of a scanning patternhaving a low FF as shown in the image (a) of FIG. 70. However, the phasehaving a high FF as shown in the image (b) or (c) of FIG. 70 may notfill all the pixels of the image. Accordingly, by overlappingacquisition signal values obtained at the pixel position of the imageobtained by controller 130 by changing the phase, the controller 130 mayobtain an image having an FF which is close to 100%.

FIG. 71 is a diagram showing that the phase of the driving signal ischanged and that a position through which the scanning pattern haspassed overlaps. In detail, the image (a) of FIG. 71 shows a path oflight when the phase component of the driving signal is not changed. Thepath of light of the image (a) shown in FIG. 71 does not pass throughmany pixels in the entire area where the scanning is performed, whichmay mean that the FF is small. The image (b) shown in FIG. 71 is adiagram showing that a scanning pattern in which the driving signal ischanged by a phase that is predetermined for the phase component whenthe phase component of the driving signal is not changed is overlappedwith a scanning pattern in which the phase component of the drivingsignal is not changed. The scanning pattern in which the phase componentof the driving signal is changed is shown by dashed lines. The image (c)shown in FIG. 71 is a diagram showing that an additionally generatedscanning pattern is further overlapped with the overlapped scanningpattern shown in the image (b) of FIG. 71 by further changing the phasecomponent of the driving signal by a predetermined phase after changingthe phase component by a predetermined phase. The additionally generatedscanning pattern is shown by thick lines. However, the thickness of theline of the path through which the scanning pattern passes is fordistinguishing various scanning patterns and may not occupy the pixelarea on the image as much as the area occupied by the thickness of theline.

According to an embodiment, as shown in FIG. 71, the phase component ofthe driving signal may be changed by a predetermined phase. At thispoint, acquisition signal values obtained at each pixel position of theimage may be overlapped with each other. Here, a predetermined phase atwhich the number of overlaps of signal values and the phase component ofthe driving signal are changed may be obtained using the aforementionedpredetermined phase change period for calibrating the phase.

FIG. 72 is a flowchart showing a process of generating one image usingan acquisition signal value obtained by the controller 130 whilechanging the phase component of the driving signal.

Referring to FIG. 72, the changing of the phase of the driving signal(S5600) includes changing the phase of the driving signal using apredetermined phase in order for the FF of the image obtained by thecontroller 130 to be 100%. In detail, in order for the controller 130 toobtain an image having an FF of 100%, the degree to which the positionof the scanning pattern corresponding to the change of the phase of thedriving signal is moved may need to be smaller than one pixel of theimage obtained by the controller 130. Here, the position of the scanningpattern may refer to a position that is indicated by a driving signal inthe image obtained by the controller 130 at a certain time.

φ_(x)−φ_(y)=2dip  [Formula 9]

Formula 9 is a formula that represents a period in which a positionwhere the scanning pattern appears is repeated by using the differencebetween the phases of the first signal and the second signal of thedriving signal. Referring to Formula 6 and Formula 7, when thedifference between the phase of the first signal of the driving signaland the phase of the second signal of the driving signal is two times apredetermined phase change period (hereinafter referred to as dip) asshown in Formula 9, the position indicated by the scanning patterncorresponding to the driving signal may be repeated irrespective ofwhether the unit frequency of the first signal or the unit frequency ofthe second signal is an odd number or an even number.

Also, when it is assumed that a is a value obtained by dividing dip,which is the position indicated by the first signal or the second signalbeing repeated according to the phase of the first signal or the secondsignal, by a certain interval (hereinafter referred to as n), the phaseof the first signal or the second signal may be changed by a. In thiscase, when the phase of the first signal or the second signal is changedby a n times, the controller 130 may obtain the same position as theposition corresponding to the unchanged phase of the first signal or thesecond signal. Accordingly, when the phase of the driving signal ischanged by a until the position corresponding to the driving signal isrepeated once according to the change in phase of the driving signal,the time required for the controller 130 to obtain an image having an FFof 100% may be reduced, and also the controller 130 may obtain ahigh-resolution image having an FF of 100%.

Here, the number of times the phase is changed in order to obtain anacquisition signal value such that the FF becomes 100%, i.e., n, may beobtained using the number of pixels of the image obtained by thecontroller 130 in the first direction or the second direction and thefrequency component of the first signal or the second signal. Forconvenience of description, the following description assumes that thephase component of the first signal is changed.

X=A sin(2πf _(x)(t+φ _(x)))  [Formula 10]

Formula 10 is a formula indicating the position corresponding to thefirst signal of the driving signal. In detail, Formula 10 may show thewaveform of alternating current in which the first signal of the drivingsignal is generated. Here, X may indicate the position corresponding tothe first signal, and A may indicate the amplitude of the first signal.Also, f_(x) may be the frequency component of the first signal, andφ_(x) may be the phase component of the first signal. Also, t mayindicate time, and the position corresponding to the first signal may bechanged over time. For convenience of description, the followingdescription assumes that amplitude A of the first signal has a size of1, which is a default amplitude, and the phase component of the firstsignal, i.e., φ_(x), has a size of zero.

$\begin{matrix}{0 \leq {\frac{X + 1}{2}*p} \leq 1} & \left\lbrack {{Formula}\mspace{14mu} 11} \right\rbrack\end{matrix}$

Formula 11 is a formula in which the position corresponding to the firstsignal is expressed as the pixel position of the image obtained by thecontroller 130. Here, referring to Formula 10, X may indicate theposition corresponding to the first signal, and the total number ofpixels obtained by the controller 130 in the first axis direction may bep.

According to an embodiment, in Formula 10, the position corresponding tothe first signal, i.e., X may range from −1 to 1 because a sine waveformis applied to the position. In this case, referring to Formula 11, therange of the position corresponding to the first signal may be set tocorrespond to the pixel position of the image obtained by the controller130. In detail, since the position corresponding to the first signal,i.e., X, may range from −1 to 1, the controller 130 may obtain the pixelposition in the first axis direction (hereinafter referred to as thepixel position corresponding to the first signal) of the image obtainedby the controller 130 along with the change in X over time by using thenumber of pixels, i.e., P.

Here, since the phase of the driving signal is changed, the pixelposition corresponding to the first signal changed according to a valuea at which the phase of the driving signal is changed may need to besmaller than the size of one pixel in order for the controller 130 toobtain an image having an FF of 100%. For example, when the value of ais larger than the size of one pixel, the pixel position correspondingto the first signal may be changed with the change in phase by a. Inthis case, the pixel position corresponding to the first signal may notbe changed from the pixel position corresponding to the first signalbefore the phase is changed to an adjacent pixel. The pixel positioncorresponding to the first signal obtained by the controller 130 may notbe obtained as much as all pixels P in the first axis direction of theobtained image. Accordingly, a value at which the pixel positioncorresponding to the first signal is changed according to a at which thephase component of the first signal is changed may be smaller than thesize of one pixel. However, the present invention is not limitedthereto, and the value at which the pixel position corresponding to thefirst signal is changed may be greater than one pixel, but the object Omay be scanned multiple times.

$\begin{matrix}{{{\left( {\frac{{\sin \left( {2\pi \; f_{x}t} \right)} + 1}{2} - \frac{{\sin \left( {2\pi \; {f_{x}\left( {t + a} \right)}} \right)} + 1}{2}} \right)*p}} \leq 1} & \left\lbrack {{Formula}\mspace{14mu} 12} \right\rbrack \\{{\left( {{\sin \left( {2\pi \; f_{x}t} \right)} - {\sin \left( {2\pi \; {f_{x}\left( {t + a} \right)}} \right)}} \right)} \leq \frac{2}{p}} & \left\lbrack {{Formula}\mspace{14mu} 13} \right\rbrack\end{matrix}$

Formula 12 is a formula indicating that the distance between the pixelposition corresponding to the first signal before the phase is changedand the pixel position corresponding to the first signal after the phaseis changed is smaller than the size of one pixel.

Formula 13 summarizes a formula indicating the distance between thepixel position corresponding to the first signal before the phase ofFormula 12 is changed and the pixel position corresponding to the firstsignal after the phase is changed.

In detail, referring to Formula 12, since a value indicated by the pixelposition of the first signal after the phase is changed is greater thana value indicated by the pixel position of the first signal before thephase is changed, an absolute value may be used to represent thedistance.

Also, referring to Formula 13, a formula expressing the distance shownin Formula 12 may be summarized, and thus a difference betweentrigonometric functions related to time and phase may be expressed usinga range that uses the number of pixels of the entire image, i.e., p.

$\begin{matrix}{a = {\frac{1}{2\pi \; f_{x}}{\sin^{- 1}\left( \frac{2}{p} \right)}}} & \left\lbrack {{Formula}\mspace{14mu} 14} \right\rbrack \\{n = \frac{{GCD}*\pi}{f_{y}^{*}{\sin^{- 1}\left( \frac{2}{p} \right)}}} & \left\lbrack {{Formula}\mspace{14mu} 15} \right\rbrack\end{matrix}$

Formula 14 is a formula indicating a value a obtained by the controller130 according to the pixel positions corresponding to the first signalbefore and after the phase is changed with reference to Formula 13.

Formula 15 is a formula indicating a value n, which is the number oftimes the phase is repeated, using the obtained value a.

In detail, referring to Formula 13 and Formula 14, in order to minimizea function shown on the left side of Formula 13, the value of the entirefunction at the initial time, i.e., when t=0, may be minimized.Accordingly, the value of the phase to be changed, i.e., a, may beexpressed as.

${\sin \left( {2\pi \; {f_{x}(a)}} \right)} \leq \frac{2}{pixel}$

Accordingly, the maximum value of the phase a to be changed such thatthe FF becomes 100% may be the value of a shown in Formula 14, but thepresent invention is not limited thereto. The maximum value of the phasea may be smaller than or greater than a. In this case, the degree towhich the pixel position corresponding to the first signal is changedmay be less than the size of one pixel.

Also, referring to Formula 14, the period in which the positionindicated by the first signal or the second signal is repeated, i.e.,dip, may be divided by a according to the phase of the first signal orthe second signal. Accordingly, the number of times the phase isrepeated and changed, i.e., n, may be calculated, and this may be avalue shown in Formula 15. In this case, n may be the number of timesthe phase at which the FF is 100% is repeated and changed. However, thepresent invention is not limited thereto, and this number may be smalleror larger than n shown in Formula 15. Here, n is the number of times thephase at which the FF of the image obtained by the controller 130 is100% is repeated and changed. Even when the phase is repeated andchanged a number of times smaller than n, the FF of the image obtainedby the controller 130 may be 100%.

Also, referring to FIG. 72, the acquisition of the acquisition signalvalue corresponding to each phase (S5610) may include causing thecontroller 130 to obtain the acquisition signal value whenever the phaseof the driving signal is changed by a while the phase of the drivingsignal is repeated and changed by the controller 130 by a n times. Indetail, when the phase of the driving signal is changed by a, theacquisition signal value obtained by the controller 130 may be stored atanother pixel position, and thus the acquisition signal values may beobtained at all the pixel positions of the image obtained by thecontroller 130.

According to an embodiment, along with the change in the period of thedriving signal by a, the acquisition signal value obtained by thecontroller 130 for the last time may be obtained for pixel positioninformation when at least one acquisition signal value is obtained atone pixel position obtained using the driving signal. However, thepresent invention is not limited thereto, and the acquisition signalvalue may be obtained at the pixel position by using the average of theplurality of acquisition signal values.

Also, referring to FIG. 72, the generating of an image using an obtainedacquisition signal value (S5620) may include causing the controller 130to obtain an acquisition signal value and a pixel position correspondingto the driving signal and to generate and provide one image. In detail,when the controller 130 obtains the image without using the plurality ofacquisition signal values while changing the phase of the drivingsignal, the FF of the entire image may not be high. Here, when thecontroller 130 obtains one image by using the plurality of acquisitionsignal values while changing the phase of the driving signal, the imageobtained by the controller 130 may be an image having an FF of 100%.

However, the present invention is not limited to the acquisition of theimage having an FF of 100% by the controller 130, and a predetermined FFmay be set such that the image obtained by the controller 130 has an FFgreater than the predetermined FF.

FIG. 73 is a flowchart showing a process of obtaining an image by thecontroller 130 by using an obtained acquisition signal value whilechanging the phase of the driving signal such that the image obtained bythe controller 130 has a predetermined FF.

Referring to FIG. 73, the obtaining of an acquisition signal value andan FF of the current driving signal (S5700) may include causing thecontroller 130 to obtain an FF using the driving signal and obtain anacquisition signal value corresponding to light emitted to and returnedfrom an object O. In detail, the controller 130 may input the drivingsignal to the driving unit 1101, emit light to the object O, and obtainan acquisition signal value using light-receiving information regardingthe light returning from the object O. Also, a pixel for which theacquisition signal value is obtained among pixels of an image acquirableby the controller 130 may be changed depending on the driving signal.Thus, when the controller 130 generates the driving signal, an FF may beobtained. Also, when the controller 130 redundantly obtains theacquisition signal value because the phase is already changed, thecontroller 130 may obtain the FF using a pixel of an image to beobtained and a pixel for which an acquisition signal is obtained.

Also, referring to FIG. 73, the comparing of an FF of an obtained imageto a predetermined FF (S5710) may include causing the controller 130 tochange the phase of the driving signal when the FF of the current imageobtained by the controller 130 is lower than the predetermined FF andcausing the controller 130 to generate an image using the currentlyobtained acquisition signal value when the FF of the obtained image ishigher than the predetermined FF. In detail, the predetermined FF may bean FF that is determined to provide an image such that the imageprovided by the controller 130 is a high-resolution image. Also, whenthe FF of the obtained image is compared to the predetermined FF, thecontroller 130 may compare an FF obtained due to the overlap ofacquisition signal values obtained while changing the phase of thedriving signal to the aforementioned predetermined PP and change thephase of the driving signal again when the FF obtained when theacquisition signal values overlap is smaller than the predetermined FF.Also, when the FF due to the overlap of the acquisition signal values isgreater than the predetermined FF, the controller 130 may generate animage using the acquisition signal values that are redundantly obtained.Here, the acquisition signal value being redundantly obtained may meanthat the acquisition signal values obtained by the controller 130 whenthe phase of the driving signal is changed overlap.

Also, referring to FIG. 73, the changing of the phase of the drivingsignal (S5720) may include changing the phase of the driving signal to apredetermined change. Here, the predetermined phase may be an arbitraryphase but may not include a predetermined phase change value at whichthe phase of the first signal of the driving signal or the positionindicated by the second signal may be the same along with the change inphase. In detail, when the phase of the driving signal is changed by theaforementioned predetermined phase change period dip, the same positionmay be indicated even though the phase component of the driving signalis changed. Thus, the predetermined phase change value to be changed maynot include the predetermined phase change period dip.

Also, referring to FIG. 73, the generating of an image using an obtainedacquisition signal value (S5730) may include causing the controller 130to generate and provide an image using the current acquisition signalvalues obtained by the controller 130. In detail, the controller 130 mayobtain one image using a signal that includes a driving signal and anacquisition signal value obtained by the controller 130 or a valueobtained by overlapping acquisition signal values obtained while thephase of the driving signal is being changed and that may indicate theposition of the pixel. Here, the obtained image may be an image havingan FF greater than or equal to a predetermined FF, and thus an imagegenerated and provided by the controller 130 may be a high-resolutionimage.

FIG. 37 is a diagram for exemplarily describing a computer system inwhich embodiments described herein may be implemented.

Referring to FIG. 37, the computer system may include a memory 10, a CPU20, and a system bus BUS configured to connect the CPU 20 to variouscomponents of the computer system.

The CPU 20 may include one or more processors and may be anycommercially available processor.

The memory may include a read-only memory (ROM) configured to store abasic input/output system including startup routines for a random accessmemory (RAM) and the computer system.

Also, the computer system may include a permanent storage memory (notshown) connected to the system bus BUS, for example, hard drives, floppydrives, CD ROM drives, magnetic tape drives, flash memory devices,digital video disks, and the like.

Also, the computer system may include one or more computer-readablemedium disks (not shown) that store data, data structures, andcomputer-executable instructions.

The method according to an embodiment may be implemented as programinstructions executable by a variety of computer means and may berecorded on a computer-readable medium. The computer-readable medium mayinclude, alone or in combination, program instructions, data files, datastructures, and the like. The program instructions recorded on themedium may be designed and configured specifically for an embodiment ormay be publicly known and available to those who are skilled in thefield of computer software. Examples of the computer-readable mediuminclude a magnetic medium, such as a hard disk, a floppy disk, and amagnetic tape, an optical medium, such as a compact disc read-onlymemory (CD-ROM), a digital versatile disc (DVD), etc., a magneto-opticalmedium such as a floptical disk, and a hardware device speciallyconfigured to store and perform program instructions, for example, aread-only memory (ROM), a random access memory (RAM), a flash memory,etc. Examples of the computer instructions include not only machinelanguage code generated by a compiler, but also high-level language codeexecutable by a computer using an interpreter or the like. The hardwaredevice may be configured to operate as one or more software modules inorder to perform operations of an embodiment, and vice versa.

Logical blocks, modules or units described in connection withembodiments disclosed herein can be implemented or performed by acomputing device having at least one processor, at least one memory andat least one communication interface. The elements of a method, process,or algorithm described in connection with embodiments disclosed hereincan be embodied directly in hardware, in a software module executed byat least one processor, or in a combination of the two.Computer-executable instructions for implementing a method, process, oralgorithm described in connection with embodiments disclosed herein canbe stored in a non-transitory computer readable storage medium.

According to embodiments of the present invention, it is possible toprovide a compact optical device configured to observe the inside andoutside of an object in real-time.

Also, according to embodiments of the present invention, it is possibleto provide a high-resolution image by correcting a phase delay occurringdue to a difference between a driving signal and an output signal.

Also, according to embodiments of the present invention, it is possibleto provide a structure for separating frequencies in each axis of anoptical fiber, a position to which the corresponding structure is to beattached, and an angle at which the corresponding structure is to beattached.

Also, according to embodiments of the present invention, it is possibleto provide a probe mounting stand for correcting the phase of an outputimage for the first time.

Also, according to embodiments of the present invention, it is possibleto provide an output image having an aspect ratio adjusted by adjustingthe voltage of a signal input to an optical fiber.

Also, according to embodiments of the present invention, it is possibleto provide a high-resolution image by adjusting the phase of a signalinput to an optical fiber.

Also, according to embodiments of the present invention, it is possibleto provide a method of finding a phase for calibrating an output imageusing a predetermined phase change period.

Also, according to embodiments of the present invention, it is possibleto provide a method of correcting the phase of the output image using adifference between light intensity values obtained at one pixelposition.

Although the present invention has been described with reference tospecific embodiments and drawings, it will be appreciated that variousmodifications and changes can be made from the disclosure by thoseskilled in the art. For example, appropriate results may be achievedalthough the described techniques are performed in an order differentfrom that described above and/or although the described components suchas a system, a structure, a device, or a circuit are combined in amanner different from that described above and/or replaced orsupplemented by other components or their equivalents.

Therefore, other implementations, embodiments, and equivalents arewithin the scope of the following claims.

What is claimed is:
 1. An optical device, comprising: an optical fiberhaving a fixed end and a free end; a first actuator positioned at anactuator position between the fixed end and the free end and configuredto apply a first force on the actuator position of the optical fibersuch that a movement of the free end of the optical fiber in a firstdirection is caused, wherein the first direction is orthogonal to alongitudinal axis of the optical fiber; and a deformable rod disposedadjacent to the optical fiber, and having a first end and a second end,wherein the first end is connected to a first rod position of theoptical fiber and the second end is connected to a second rod positionof the optical fiber, wherein the first rod position and the second rodposition of the optical fiber are positioned between the actuatorposition and the free end, wherein the deformable rod is substantiallyparallel to the optical fiber from the first rod position of the opticalfiber to the second rod position of the optical fiber, and wherein, inthe cross section perpendicular to the longitudinal axis of the opticalfiber, the deformable rod is arranged such that an angle between avirtual line connected from the first end of the deformable rod to thefirst rod position of the optical fiber and the first direction iswithin a predetermined angle, whereby the movement of the optical fiberin a second direction perpendicular to the first direction is limitedwhen the free end of the optical fiber moves in the first direction asthe first actuator applies the first force on the actuator position ofthe optical fiber.
 2. The optical device of claim 1, further comprising:a second actuator configured to apply a second force on the actuatorposition of the optical fiber, wherein the second actuator induce thefree end of the optical moves in the second direction.
 3. The opticaldevice of claim 2, wherein the optical fiber vibrates by the first forceapplied from the first actuator and the second force applied from thesecond actuator and moves corresponding to a Lissagjous pattern inaccordance with a predetermined condition.
 4. The optical device ofclaim 2, wherein the optical fiber has a first rigidity and thedeformable rod has a second rigidity.
 5. The optical device of claim 4,wherein the deformable rod changes the rigidity of the optical fiber forat least one of the first direction and the second direction when theoptical fiber moves in accordance with the first force and the secondforce.
 6. The optical device of claim 5, wherein the optical fiberdrives different resonant frequencies with respect to the firstdirection and the second direction.
 7. The optical device of claim 1,wherein a length of the deformable rod is shorter than a length of theoptical fiber.
 8. The optical device of claim 1, wherein the first endof the deformable rod is fixed to the first rod position of the opticalfiber by a first connector and the second end of the deformable rod isfixed to the second rod position of the optical fiber by a secondconnector.
 9. The optical device of claim 8, wherein the first connectorand the second connector moves as the optical fiber vibrates.
 10. Theoptical device of claim 2, further comprising: a controller configuredto apply a first driving frequency to the first actuator and a seconddriving frequency to the second actuator.
 11. The optical device ofclaim 10, wherein a difference between the first driving frequency andthe second driving is more than a predetermined range.
 12. The opticaldevice of claim 1, wherein the predetermined angle is below +a ° and −b° about the first direction.
 13. The optical device of claim 12, whereinthe a ° and b ° have different values.
 14. The optical device of claim12, wherein an absolute value of a minus b (|a−b|) is below 10 about thefirst direction.
 15. The optical device of claim 12, wherein an absolutevalue of a minus b (|a−b|) is below 5 about the first direction.